Title says it all. If the target line in a spell descriptor says "one creature" or something like that, can you cast it on yourself? I'm pretty sure I know the answer, but I'm looking for confirmation.
Unless the spell that affects creature specifically states that it cannot be cast upon oneself it can, so yes, that one creature might be the caster himself.
That's what I figured. I was thinking of buff spells when I asked, but now that I'm thinking about various spells more, I'm coming up with some highly theatrical ways for wizards to commit suicide.