I've been thinking I really need to get back to my spring powered arrow driver project which I posted about in this thread:

http://slinging.org/forum/YaBB.pl?num=1558440095

Whilst looking into different trigger mechanisms, I found this French forum where a user has posted a lot of different mechanisms with really detailed graphics and animated gifs. Honestly, a lot of them seem unnecessarily complicated and would probably have a pretty high failure rate. That being said, it is interesting to see just how complicated a crossbow can get :D

http://www.webarcherie.com/index.php?/topic/16046-m%C3%A9canismes-de-d%C3%A9clenchement/page/1/