I used to have about 100 to 150 three character .com's in my portfolio. I recently sold off every one I had in the price range of $80 to $150 each. I had some really good ones and some really bad ones. 3 character .coms are a niche market that I am not sure I would get back into.
The REAL reason I liked them was because you could always evaluate what the minimum value was. There were times when you knew that if you wanted to sell any 3 character .com you had on this board for a minimum of $60 (example), you were guaranteed to get that price. They had a DEFINATE value. During that time I could search around for them and pay more or less $40-50 each. To know they I could do a quick flip for $60+ was a pretty good thing.
It was fun at the time and was a good break from buying generic .coms and trying to evaluate or guess their value.