[tom_]

It's my first port of call, as it's rare for me to run the code I'm working on outside the debugger. So if anything goes wrong, it's there. If nothing else I can set a breakpoint or two to check that particular points are being reached, and have a look at some variables to see if there's anything obvious.

Also very good for crashes or asserts or whatever. The offending line, and the stack trace, are shown immediately.