You guys suck, I once answered the door still covered in soap suds.
If I'm expecting someone to call or come over while I'm in the shower, then I'll answer the phone/door. Otherwise I'll probably just ignore it. But regardless, I'll usually just answer the door in whatever I'm wearing. Sometimes I like to hang around my place with my pants off, so if someone knocks at those times I'll put some pants on. But I've answered the door in a towel lots of times, and just in a shirt and boxers (which is what I sleep in). And I was serious about the soap suds thing.
You Can't Kill What You Can't See
-Beware of the FantomJedi