I have been more and more impressed with Wine — it seems to be a pretty mature product these days. The number and type of Windows programs that I can install and they Just Work, and perfectly, is very impressive.
To date, here are useful programs that work:
Ultra Fractal, version 2
Crack Attack - this has a Linux version, but the one installed wasn't compatible with the Windows version on my sister's computer. So I installed the exact same one as hers to make sure, and it worked.
Armagatron Advanced — this is especially impressive as it is intensive OpenGL, and the performance is just as good running under Wine as the Linux version.
Internet Explorer 4, 5 and 6 — need to be installed using IEs4Linux
Inno Setup (v4.1.4, less luck with more recent versions)
LOGOS - E4's Bible Study Library (a very old version)
I'm quite impressed, and it means that more and more I just expect Wine to be able to handle things right out of the box, when in the past it was a bit of a victory to get the simplest application to run.