Absolutely. Kamikaze tactics were not limited to aircraft, and included both sea and land manifestations.

First up is the 'human torpedoes', the main type of which, Kaiten Type 1, was developed in early 1944, and basically a 3400 lb torpedo modified to include a compartment for a pilot to sit inside. The plan was that a larger submarine would carry several of these and release them near American shipping, with the pilot guiding them to their final target with considerably better range and accuracy than could ever be hoped for with a conventional example. The Type 1 had several issues, especially leaking, but while several hundred were built, programs to create improved models never yielded production numbers.

The Kaiten was put into operation in late 1944, with the first successful attack taking out the tanker ship USS Mississinewa in late November. One of eight Kaiten carried by the parent sub in the attack on the American fleet at Ulithi Atoll, it was the only one to strike its target (and three had malfunctioned before they could even be launched), but in a rather funny twist, being a taker, the amount of smoke from the wreck led the parent sub to believe that possibly all of the suicide attacks had succeeded, and reported total success upon her return. The result was that the Japanese now assumed they had a super weapon on their hands, and duly dispatched six parent subs for a massive coordinated operation to be launched in mid-January. Not a single American ship was sunk, but once again reports of success came back, and the Japanese believed that 18 Kaiten hit their mark. Japanese submarine missions continued to focus heavily on Kaiten missions through early 1945, and continued to be mostly futile, with little success and often resulting in the loss of the parent subs as well. The minor success in sinking the USS Underhill in July would be the last Kaiten to sink a target, and five other American ships possibly sustained damage from Kaiten, (although only one, the USS Pontus H. Ross, seems to be certain) all in all a very low success rate for the 147 Kaiten sent out by the Japanese fleet.

More robust midget submarines were also prepared for suicide missions, the Koryu and Kairyu, but they were held in reserve, with the intention of launching them from the coast against the American invasion fleet once it reached Japan's shores, and thus never went into operation.

The final seaborne Kamikaze method the Japanese worked on were "crash boats", which are exactly what they sound like - small surface craft which would race forwards to slam into American ships and take them out. In comparison to the Kaiten, which required the "expenditure" of a skilled sailor to drive it, the crash boats could be manned by teenage recruits. As was so often the case with the Japanese, dueling projects existed as both the Army and Navy developed their own crash boats and didn't share well with others. The Navy's single-pilot Shinyo Type 1 Mod 1 was not even 20 feet long, and could carry its 595 lb charge towards the target at 23 knots . Some were fitted with a small 120mm rocket launcher, which was hoped to distract American gunners momentarily and help the ship reach its target, and possibly add to the damage dealt. The lead ship of a attack group would be the slightly larger Type 5, which carried a second sailor manning a 13mm machine gun. The Army program resulted in the quite similar Renraku-tei, or Maru-re, which in theory "only" went along side the enemy ship and dropped two depth charges, but while in theory could then make an escape, was functionally just as deadly to the driver.

First deployed in the Philippines in late 1944, over 6,000 crash boats were built. The first deployment was not auspicious however, as one boat caught fire in port, exploded, and led to several more of the craft to blow up too. The boats would enjoy limited success moving forwards, with one representative attack in Corregidor resulting in only three sinkings despite sending 60 Shinyo out. Similar results were demonstrated at Okinawa and Iwo Jima, where, despite several hundred craft present, results were mild, both sinkings and damaged targets being in the single digits. Several thousand remained when the war ended, held in reserve to combat the expected invasion.

Thats about it for ships, but it there still remains one more method of suicide attack to mention - the simple human variety. At sea, Frogmen trained with the use of the Type 5 Attack Mine, which would be struck on the hull of American ships and explode on contact, hopefully taking out landing craft as they approached Japanese beaches. They were referred to as "Crawling Dragons", since they would have no fins, but instead be expected to wear weight belts and just walk along the ocean floor. Planners wanted 6,000 Frogmen trained and ready to take on the invaders, and while 4,000 were either trained or in the process by late summer, the end of the war precluded their deployment. On land, similar tactics were developed for taking out tanks, using magnetic charges or satchel charges. Various methods of deployment were used, including a backpack that the soldier would wear when he threw himself under the tank, or the "lunge mine" which was attached to a long pole and used a contact detonator. Japanese soldiers did enjoy some success against American tanks with these methods, but hardly enough to turn the tide obviously.

Sources

Kamikaze: Japanese Special Attack Weapons 1944–45 by Steven Zaloga

Kamikaze Attacks of World War II by Robin Reilly

There were two main types of suicide craft used by the Japanese Navy: the Kaiten human torpedo, and the Shinyo explosive motorboat. The Japanese army operated the Maru-ni motorboat, which was not designed as a suicide weapon, but in practice often was.

The Kaiten was a Type-93 torpedo, with an enlarged section for a pilot. These were generally carried to a target by submarine, which would carry 4-6 of them. The cruiser Kitakami was converted to carry them, but never carried out an attack. Kaitens launched from submarines sank several ships, including the oiler Mississinewa and destroyer escort Underhill.

The Shinyo explosive motorboat was an 18 meter long motorboat, with a large explosive charge in the bow. The Maru-ni used a similar hull, but was equipped with a pair of depth charges, set to go off at a shallow depth - this was theoretically survivable, but rare in practice.They were generally used as point defense weapons, operating from caves covering landing beaches and harbours. They scored some success in the Philippines, sinking a few landing craft and a sub-chaser. They were also used at Okinawa, where they damaged a transport and two destroyers, as well as sinking several landing craft. These were based in Hong Kong, on Lamma Island. Due to a miscommunication, this base would be accidentally attacked by the RN on the 30th August 1945 - the RN were arriving to repossess Hong Kong, and misidentified a Japanese motorboat as a suicide attack.

Explosive motorboats would also see use with the Italian navy. These weren't suicide weapons, as the pilot was expected to bail out before impact. These were a more offensive weapon, being towed or carried to enemy harbours before being launched against moored ships. They saw one of the biggest successes of the explosive motorboat, disabling the British heavy cruiser HMS York at Souda Bay in Crete.

Sources:

Shinyo!, Robert Hackett and Sander Kingsepp, http://www.combinedfleet.com/ShinyoEMB.htm, 2011

Kaiten Special Attack Submarine, http://combinedfleet.com/ships/kaiten

There were a large number of official and ad hoc vehicles used for "special attack" ( the Japanese euphemism for suicide missions). The caves were likely launch sites for Shin'yō motor boats, some of which were deployed to Hong Kong Besides motor boats, there were manned torpedoes, rocket bombs, Infantry with mines, and in one case in Luzon, obsolete tanks with a charge attached to the front that would detonate when it crashed into an American tank.