Heads up for Corpclave (as advised by the wonderful cigar chompin' zombie killin'/killed by Josephus), go take the interview at the MU (MU on the map, too!) when next you sneak in. Look it up on the wiki for how to do it. When you start the interview, everything's pretty straightforward but the two slightly tricky answers are Muut! entertainment (muut? Well, probably. Lmap it, the answer is in the lmap) and Heaven. Then you can get into corpclave whenever.
WU.
Weyland-Utani, like in the Alien films except Utani instead of Yutani. And as such the entertainment subdivision is WUUT. Heaven is still Heaven however, and apparently this big megacompany feels the need to send a space mission to a bar in Gangland.
If you get any question 'wrong', just walk out of the room with the interviewer and walk back in. He'll reset.
As for working in there, a few things can be done. You can go into the IT room (I think it's on level 5, correct me if I'm wrong) and use a hacking device to jack into the servers there. Fix them and you'll get job points. Good hacking experience.
You can also, for the same job, wander around the halls until you hear one of the NPC's whining about how he needs a particular object, and if anyone's going to the storage closet. Look around the hall until you find a storage closet. They're pitch-black places, but you can scavenge in them without a light, just keep searching until you find the item they asked for and then hand them the item. Again, job points.
Yet another way of earning points is to look around for fax and copy machines and fix them. Good repair experience.
The final way that I know of is to hang around the main business floors (5 and 6, I believe) and wait for someone to say something about doing a post-mortem on a report or whatever. Talk to them and mention the word 'me', and they'll pass a report off to you.
This is the fun bit. You need to find someone in the company that you can blame this report on. Doing so will net you an IP or two in persuasion, and if you blame it on another player they'll get persuasion IP as well (even if they resist and deny responsibility for the report).
All those get you money and points towards completing the office worker job, but there are some other things you can do too.
The W-U building generally has a lot of NPC's in it during normal working hours. These are regular people just like 33Jim and 12Steve, and they have needs. One big difference between them and the people on the street, however, is that they're almost all loaded with cash.
So give them soylent bars, start a little nookie, or wander around coughing like mad and then cure the black lung when they get it. You can make a nice sideline by squeezing the cube rats for their cash.
Also of note is that there's a coffee machine on the 6th floor that you can get free coffee from. I have no idea how that thing works, so I'll just assume that it's a magic coffee machine that generates a batch of 10 coffees every so often. Quite handy for when you need coffee, which is of course always.
I'd like to take up ghostbusting, but the wiki says that proton packs need at least 4 raw in science in order to use effectively. That could take a while, especially with nothing to grind it up on first... They're probably horrifically expensive too. Suppose I could use EMP grenades, but...
EDIT: Wait, wiki says that in order to use a research simulator at all, you need at least 1 raw in science.
If a simulator needs 1 raw and a proton pack needs 4 raw, how the hell are you supposed to grind science? Provided you
didn't tag it during character creation, that is.