Telling mice apart

This may seem like a strange question, but is there any way of marking mice to tell them apart to keep up with which females are having larger litters, etc. Several of mine are albinos, and i cant tell them apart. I know of one way that i saw used on lions, but i cant bring my self to do it. Any ideas?

you can take a permanent marker and mark their tail. it'll wear off, but as long as you keep making the mark again when you see it fading....

Any other ideas anyone? (that one sounds like a good plan though, and ill probably go with it)

If its really that big a deal you could just tattoo the ears. I simple needle in non toxic ink sterilized first when they are really young. I have heard of a few breeders marking their stock like that

put them in seperate cages?...the marker idea seems good

I arrange mine by which ones look ready to be eaten first:D