Leggman, I'm in the same boat - I would love to have a mill, but a) the Bridgeports etc. are too large for the space I have, and b) even used ones cost several times the $$ I can free up.
I do have a milling attachment for my 1947 9" South Bend lathe, and it will do small jobs, but it's not as good a solution as a stand-alone mill. I've been looking at Chinese mini-mills, like the ones that turbo_bird was mentioning. The same model seems to be available from many different sources with different branding, but all seem to be in the same general price range and, as Driven5 points out, metal replacement gears (and belt-drive conversions) are available for them. They seem to be popular enough that there is tons of info on the 'net about them, forums etc., so they're a "known entity". At this point, I'm waiting for a point where I have enough spare cash to divert to one of these.
There are various differences among the Chinese mini-mills, such as the taper (some are MT3, some are R8, etc.), so that would be one thing to consider. I really don't know which is better, yet, so...
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