Pine-Sol is widely available, cheap, smells good, and I hear it can also be used to clean floors, although I don't have any personal experience in that area.
Here's a picture of a recently purchased batch that needed the paint removed:
These had been primed with spray enamel primer, then painted with a mixture of enamels and acrylics, and then in some cases had sand glued on their bases for texture. I pulled off any loosely glued parts for re-gluing later.
Into the Pine-Sol they go:
I use plastic containers with tight fitting lids, this one is from some sort of sliced deli meat product. I let them soak for about 24 hours, then I took the container to the kitchen sink and washed off the Pine-Sol with warm water and used a soft brass bristled brush to gently scrub any paint that had not just fallen off into the sink. Put the sink strainer in the drain or you may lose something down into the disposal, I hate when that happens.
Remember to wash out the sink when you are done or you'll hear about it from your significant other!
I let them dry on a couple of paper towels with a fan blowing on them and this was the result:
I think they look pretty good, and are ready to be primed and painted and added to my forces. I hope this article is of use to any of you Ogre miniature gamers with similar issues.