This just happened. I am working on clearing my mail box, when I got a repro for a high CPU load from a user.
Spent an hour trying to figure out what is going on. Found that the problem is something with map/reduce under extreme load.
Couldn’t figure it out. Went to bed depressed after midnight.
Got up at 4 AM, sat down on the same problem. Solved it (root cause, that @ayende guy doing O(N Scary) stuff) in under 15 minutes.
Now I need to figure out what to do with the rest of the night.
Also, currently in Denmark (Copenhagen) and it is bloody cold out here. This is what I look like when I am cold: