Speaking of readability, here's an entertaining one I've been seeing more of in C:
if (result == SUCCESS)
if (SUCCESS == result)
The rationale behind the second is that you don't end up accidentally assigning SUCCESS to result (eg, if (result = SUCCESS)). But I know that I find it weird to look at it the other way around. I want to know if the result was successful, not if successful was the result. Maybe it's an english thing.
I know that Xcode has been putting up warnings/errors for code that does assignments in if-statements and saying that if you really want to do that, wrap it in an extra layer of parentheses (eg, if ((booleanResult = Do_Something()))). I'm not sure this is somehow more clear that you're doing the assignment...