Pleasure Island at Downtown Disney is amazing! You can choose to pay for admission to one club—the cost was $10 at the time we went—or you can get an unlimited club pass for the evening for $22.
The unlimited club pass was definitely worth it to see what fits your style, and it was also great to be able to go to the comedy clubs when we needed a break from dancing.
My favorite was "8 Trax," a disco and '80s music club that plays videos of the songs. They also do the YMCA every night at midnight—so it was fun, and not embarrassing to be cheesy.
The "Comedy Warehouse" is a fantastic improv comedy club. I am not normally a stand-up comedy kind of gal, but I was laughing so hard my sides hurt.
I did not care for the Adventurer's Club very much, it is supposed to be a comedy club too but was not as funny.
Other clubs included:
1. Rock & Roll Beach Club—They have live bands here sometimes
2. Motion—Top 40 dance club
3. Mannequins—Techno/Electronic Music, this club has a spinning floor
4. BET Soundstage—Rap/R&B Music
Most are 18-and-over and some are 21-and-over on certain nights, so check the website for details. They are very strict on fake ids and underage drinking, we saw several people get busted there, so don't try it!
All of the clubs have specialty drinks that you can buy, but I did not try them.
Parking is free, and the hours are 8pm to 2pm. They have shuttles if you are staying in a WDW resort property.