O'Shea's may be the coolest place on the strip.  It tends to draw the younger crowd, probably for the beer pong and cheap beer.  Drafts are usually $1 or $2.  Sometimes they have live music.  It's not big like the hotel casinos, and it's a little dirty, but I guess that's the way I like it.  Great place to get hammered and play beer pong, and maybe lose an article of clothing in the process.  Love it.