Pocket D is a dance club in another dimension where heroes and villains can gather peacefully. It has a variety of amenities and is used for many yearly events (usually Christmas, new years, and valentines)
On some servers, the dance area is constantly being used to socialize while on others, it's empty and forgotten. But even if there aren't other players, there are tons of reasons why going to Pocket D is awesome.
Quick Travel
On the hero side, there are 4 entrances to Pocket D. On in Talos, in Kings Row, in Founder's Falls, and Faultline. Entering any one of these leads you to a small "zone hub" that lets you exit in one of the other zones in just a few seconds. It's sometimes the quickest way to get from one zone to another and is one of the best ways to get to Faultline which doesn't have a train or market to teleport to.
For villains, PD connects to Port Oakes, Sharkhead, and St. Martial. It's not usually the fastest way to travel except at low levels and as a de-facto Mercy Island teleporter since the entrance to PD in Port Oakes is right next to the Mercy Island ferry.
Amenities
Pocket D is full of stuff for you to use! Check it out:
Inspirations
There are several bartenders throughout the club that will sell you inspirations. If you are near Pocket D (or have a telepad or PD teleport power), you can pop in there for inspirations.
Superbase Portal
If you don't have a base teleport power, if your teleport is cooling down, or if you happen to be in PD already, this superbase portal comes in very handy.
Note that if you stand very close to the portal, you can earn the "monitor duty" day job badge.
Vault
I for one don't use the vault, but if you do, here's one. The key is if you're filling up on salvage and are passing through anyway, why not dump some of the good stuff here until you have time to go sell or craft them?
This area counts towards the Banker day job badge.
Arena
Did you get into a heated argument with someone that cut-in on the dance floor? Settle it right away in the Monkey fight club/arena outlet! Sadly, this area doesn't count for a day job badge, but it does work in all other respects like the arena terminals elsewhere in the city.
Hospital
These are only used when there are events and missions available in Pocket D, but the neat thing is that the hero hospital (but not the villain one for some reason) counts for the Caregiver day job. If you've been counting, that's four different day job badges you can get in the same small area!
And if you get the Pocket D teleport power, it's like having an Arena/Base/Vault/Inspirations purchase teleporter.