Had a call back about 4 - 5 months ago on a repair; we finally figured out the leak wasn't @ the chimney bump out / siding to decking joint, it was water splashing up upon hitting the ground & getting under the siding of the house (his flashing was "teh suck", so it really needed some love anyhow).
I have a house in San Antonio to visit as soon as we can get down there - just got the call the other day. He said it's on a chimney & this house is all shiplapped decking with a somewhat crustied up flashing setup. On this one, he'll have to pay for the visit 'cause I tried to talk him into a repair when we first did the roof back in October '06.
& Of course I'm sure some of you remember my triple play of return trips with the skylight leaking (bad flashing kit, too shallow on the factory setup as supplied by the customer). We finally got that one squared away & I really should have charged for all the return trips.