Please keep in mind that "Yes, _____ was flying before the war ended" is not an acceptable answer by the standards of this subreddit! Please go into a little detail about the operational history at the very least!

The Arado Ar234 was a German jet bomber which saw service right at the end of the war (from August 1944), mostly in a Recon role.

In addition, the Messerschmitt ME-163 rocket powered fighter saw limited service as an interceptor (starting May 1944), although all accounts that I have read about it have left me thinking that it was more a death-trap than an interceptor. -It had a bad habit of finding a final reserve of fuel (hydrogen peroxide) just as it landed, resulting in spectacular and often fatal crashes.

There was also the Heinkel He 162, which just made it into service in April 1945. It was designed and built quickly, and mostly constructed of "non-strategic materials" - in other words, wood. It's a really weird-looking plane with a single jet engine sitting on top of the fuselage, and wasn't terribly successful.