I couple of days ago, I came across ExtraTasty.

Extratasty.com is a web site devoted to drink making. You can comment on drink recipes and submit your own. It will give you cocktail recipes based on the ingredients you all ready have. You can also search by tags, title, etc. As recipes are added, the site will grow. 

You can either create an account to create and save your bar, or just enter the details every time you want to find a cocktail.

What are you waiting for, get out all those strange drinks in your cupboard and start making cocktails!!!