Gif Central boasts hundreds of funny animated gifs. Only the best of the best make it onto this site, with most of them having an accompanying source. No tumblr-esque one-second-long disappointments. No obscure titles or descriptions.
This is a funny animated gif of a guy in an exam reading the words "You can do it" on his hand. This is from the 5secondfilms video "Test Notes". Seen this with the clever title "Motivational Cheating".