Well, I'm writing this on a POS Win98 box running Opera 7.23 (registered), but my main machine is an Amiga 3000.
I use it for occasional video work, but my bread and butter is mySQL and Cold Fusion programming, with web development on top.
All of the business' day to day work is done on it, mostly in CED, YAM, Final Writer, TV Paint, IFX, AdPro, PPaint, TurboPrint, TurboCalc... on and on...
Invoicing and accounting is done on the 3000, as is all database design, CF programming etc. Its much faster and stabler than any version of Windows I've used thus far (2.0, 3.1, W95, W98, W2k, WXP..), so I'll probably keep using it until I have to switch.
The win98 box is for testing, surfing and DE/AA development.