We've all been there (usually when we are young and inexperienced).

Fixing it properly is too difficult, too risky or too time-consuming. So you go down the hack path. Which hack from your past are you most ashamed of, and why? I'm talking about the ones where you would be really embarrassed if someone could attribute the hack to you (quite easily if you are using revision control software).

One hack per answer please.

Mine was shortly after I started in my first job. I was working on a legacy C system, and there was this strange defect where a screen view failed to update properly under certain circumstances. I wasn't familiar with how to use the debugger at this time, so I added traces into the code to figure out what was going on. Then I realised that the defect didn't occur anymore with the traces in the code. I slowly backed out the traces one-by-one, until I realised that only a single trace was required to make the problem go away. My logic now would tell me that I was dealing with some sort of race-condition or timing related issue that the trace just "hid under the rug". But I checked in the code with the following line, and all was well:

printf("");

Which hacks are you ashamed of?