If you can't bolt it to the floor, bolting it to the ceiling does seem like a reasonable option!
Your idea of pulley and counterweight has precedent, I think; I think I've seen pictures of old drill presses with that kind of setup.
Another option might be one (or more) of those gas springs used on vehicle tailgates, if you can find one with enough oomph. I like the counterweight idea for its simplicity though.
[This message has been edited by SGW (edited 09-07-2002).]
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