During Jazz on the Ave (a monthly festival we have here in Delray) I wandered down to Elwood's for a cheap drink during our bar crawl. And they do have cheap drinks, like a $2 domestic beer on tap. They also have grungy seating and it's basically a reworked garage. With some booths and plastic chairs out front, on a concrete slab.
Elwood's is as casual as it gets. Let's just say it's not the type of place you order a mojito, as friend of a friend wanted to do. Lots of bikers like to go here and park along the side street, which has parking for bikes. But it's not a rough crowd, everyone I have run into here has been friendly. They also serve food, but I have never tasted it. I've heard it is decent.
They have an Elvis impersonator performing on Thursday nights, and most other nights they have a blues or rock-a-billy type band playing.