Here's a lovely little one that just took me much to long, probably because I'm tired, or having an off day or something:
Select [Name]
[Surname],
[Address],
[Telephone],
[Email]
From ATableAboutPeople
See, the error isn't obvious, because the SQL compiles and runs, but the result set just doesn't bring back what you expect.....because [Name] is now aliased as [Surname] - all because of a missing comma.
Hate it when that happens.