Well, as far as my rep knowledge goes:
Basic everyday watch: Go with an Ultimate PO (choose Swiss ETA if you have 120 bucks to spare, go for Asia 21J if you can find someone to replace it (if it dies) and if you feel lucky). Personally, I just love the rubber strap as it kind of goes well with everything, from jeans to a (daytime) suit. A Seamaster Professional is also an option here, as well as a Bell & Ross Instrument or Tag Link (bit more fashion-y).
Dress / Business watch: A lot of great ones to get here, the Hublot Big Bang is a beauty, though expensive (Wallpaper magazine selected it as best watch of 2007). Also, I like the Breitling Navitimers and and Montblanc Timewalkers, although the Asia 7750 movement is a pain in the ass, most people would agree. So make sure to find a friendly watch smith to oil / fix these (if they die on you) before you buy. Panerai watches are also a great choice, definetley if you are into watches that are more minimalistic in design.
Showoff / Black Tie Watch: Some people would consider a Big Bang or Panerai here, while I wouldn't. They are just a bit too flashy for my taste, definetley if you are suiting up a dinner jacket or nice suit for some special event. The two tone Breitlings are lovely here, just as the IWC Portugese (although the 7750 with seconds at 6 seems to be incredibly unreliable).
Have you noticed I haven't mentioned Rolex? It's because I just don't like their style, they are a little too shiny for my taste and of course, everyone with little sense of taste and a bag of money seems to buy a Rolex, as it's sort of the safe way to go. Don't get me wrong, some people here love Rolexes and I myself think the Sub and Daytona are not bad at all, but I'm into more elegant, minimalistic watches.