WINE is the free (beer and speech) original that spawned Cedega (aka WINEX), which is more of a WINE that's specifically tailored for gaming. Cedega costs $15 for the first three months, and from then it's $5 a month if you want to maintain the ability to get updates. If you wanted to, you could not continue to subscribe and just stick with the version you last downloaded in the three month period.
There are a bunch of guides around on getting particular games to work with WINE/Cedega, and there are also a bunch of installers to get a few Windows games running natively in Linux (Google "loki installer" - the Linux version of Unreal Tournament 2004 outperforms the Windows one on this rig).
Whilst the anecdotal evidence seems to be that WINE (and especially Cedega) seem to work remarkably well, "hit and miss" seems to be a fairly apt description of Windows gaming in Linux. The most successful solution seems to be keeping a Windows partition around just for those Windows games you really must play.
PS: I just woke up so feel free to correct me if I've misstated anything.
There are a bunch of guides around on getting particular games to work with WINE/Cedega, and there are also a bunch of installers to get a few Windows games running natively in Linux (Google "loki installer" - the Linux version of Unreal Tournament 2004 outperforms the Windows one on this rig).
Whilst the anecdotal evidence seems to be that WINE (and especially Cedega) seem to work remarkably well, "hit and miss" seems to be a fairly apt description of Windows gaming in Linux. The most successful solution seems to be keeping a Windows partition around just for those Windows games you really must play.
PS: I just woke up so feel free to correct me if I've misstated anything.