235,000 Italian personnel served on the Eastern Front, although the majority arrived after the tide had already turned. Perhaps this bought Hitler an extra week in the bunker, which might've helped Eva Braun to achieve her strategic objective.

Once the Germans took control of Axis forces in Africa, Rommel was able to put some of the elite Italian units to good use.

Perhaps the biggest contribution was the fact that, for a time, Allied merchant shipping had to go all the way around Africa rather than cutting through the Med.

Or - an argument could be made that Italian participation had an important political effect; legitimizing and strengthening Germany's diplomatic hand.

Overall, Italian participation was probably more of a hindrance for the Germans. However, I'm of the opinion that Italian participation could've won the war for the Germans if it had been coupled with an invasion of Spain and the capture of Gibraltar, but that's a story for another sub. EDIT Oh yeah, and invade Malta, for Pete's sake. That should've been a no-brainer. EDIT 2 Why Spain and Gibraltar?