Matt Lewis, who plays the character of Neville Longbottom, has started his own Twitter account – http://twitter.com/Mattdavelewis. He talks about the popular micro-blogging service in this video:
Other Harry Potter actors on Twitter? Well, Tom Felton for one – you can follow him at http://twitter.com/tomfelton.

he has become real cute, hasn’t he!
omg funniest thing ever. i like it when he bags his mate lol. i have the same ghostbusters shirt as him (: