damn it i have gnats coming from somewhere in my apartment. they are driving me crazy. its not like there are a ton of them but i keep killing them one by one. i only see them one by one too. it's like i kill one and then another one will fly by. i've cleaned up the whole place and they are still here!!!
They're probably actually fruit flies. Make sure you have the trash taken out and that there's nothing hidden in the back of a cupboard somewhere that they could be reproducing on. Had a bad problem with them once when my roommate forgot about a bag of potatoes in the back of our walk-in pantry. Couldn't figure out where the buggers were coming from until I found the bag of nasty, moldy, runny things that used to be potatoes...