The 'Mean Girls' star and the 'Half Nelson' actor – who split last April after dating for two years – were reunited at Los Angeles' Green Door lounge, where Ryan made his DJ debut.
An onlooker said: "Rachel and Ryan talked when he was away from the deejay stand. They really looked like good pals. He seemed happy to see her."
Ryan is a big music fan, and has signed up to perform at the exclusive nightclub every Tuesday for the foreseeable future.
A source said: "DJ-ing is a pretty new thing for Ryan. He's been messing around. He's really into music, and he's a fan of the night."
The 27-year-old actor played music from the 40s and 50s and wore a white T-shirt, black trousers and leather motorcycle jacket for his set.
Other celebrities who went to see Ryan's debut included Oscar-nominated actress Catherine Keener, US actor and singer Shane West and hockey player Sean Avery.
©2008 AOL Australia Pty Limited in association with Bang Showbiz.All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
Related Article: Kirsten Dunst and Ryan Gosling Make Their Relationship Public
