Originally Posted by EBORG9

Bare- Mirage
Venus- Cesar's Palace
The Beach - Mandalay Bay

There are a few more, some are "Tops Optional".

These you can get in by paying a cover, and are separate from the "free" pool for hotel gusts. Most others require you to be a guest, unless there is a designated event open to the public.

Cover into a Pool Lounge is still around $20-$30 for guys, depending on if it's topless.