I found a fun VS 2005 bug today:

1. Run an application with an assert that’s hit
2. Bring up the JIT debugger, based on Windows/Studio prompts
3. Edit and save a file while (or after) debugging from that VS session
4. If the file’s name was mixed case, Studio will save it in all-lowercase (and now you have 2 files with similar names)
5. The new file will also have its line endings munged/reversed/mixed

I’ve seen this bug before, but have never been able to reproduce it reliably. Reverting it, of course, requires moving the changes to the original file by hand (or the diffs will be messed up).