I don’t always listen to music when playing Cata, but when I do, I have a WinAmp mix. To the best of my recollection:
There are some ambient tracks (Clannad, HoMM3, MGS1) for my base, some exploratory tracks for exploring (MGS1, VtM:Bloodlines, C&C:RA2), some combat tracks for fighting (MGS1, Bloodines, UT2k4) and some Ominous tracks to use as needed (Precursors, UT2k4).
Stay amused, my fellow Cata-players.