Maintenance is usually finished by the time I log on to WoW. The only time maintenance cuts in on my playtime is when it's an "extended" maintenance that goes on for like 12+ hours if something goes wrong. I only play WoW in late evenings, so maintenance is usually long finished.
If WoW is down in later evenings for some reason, I just play other games. Usually something on Steam. Killing Floor (zombie killing) and Chivalry (PvP free for all/capture the flag stuff in a medieval setting) are usually my favorites.
Or sometimes I'll just get drunk and watch a movie.