Spell Check Catastrophe

Or very nearly one. I was writing to a girl from Yahoo Personals who asked me if I play my own songs or mostly do covers. What I was trying to write was

I do some of my own stuff, but I'm such a slow and sporadic songwriter that mostly I play covers.

But because I spelled sporadic, sparatic, spell check tried to make the sentence:

I do some of my own stuff, but I'm such a slow and spermatic songwriter that mostly I play covers.

I'm not sure what a spermatic songwriter is, but it sounds messy, and certainly not how I want to identify myself.