If you've just had your third dot-com shot out from under you, there's a place you can go where everyone understands. Really. Everybody at a Pink Slip Party is looking for work, except for the companies and headhunters who are on hand to network with the recently axed of the high-tech world. This relaxed alternative to the cattle-call job fair is becoming increasingly popular as more area employers drop more human resources with less warning. One recent party at Brooklyn's drew about 275 job-seekers; there's another planned for April. Organizers at LH3, Inc., a PR/marketing firm, plan to continue the parties as long as there's a need. And with the economy tanking, it seems that people will be seeing pink for a while.