One of the reasons I like to come to work late and leave late - in the evening there's always a conference room available to hide in and do some productive work, and there's even a good chance that by 5PM, all my cow-orkers will be gone, so I'll have the whole office room for myself to either work or take a nap first and then continue to ~8 PM.

My SO doesn't approve of this schedule though, so I do this only on days we're not going to see each other.