Do you need interchangeable lenses? Have you used a rangefinder?
If you dont know the answer to the first, and you say no to #2 question, drop $25 on any Konica/minolta, whatever- rangefinder (c35 autos2, etc). Try that out, if you just love it after 5 or 10 rolls of film and dont find yourself headed back to your SLR, then start the search for a fancy [$$$] rangefinder. Also remember that the viewfinder will be off when you get away from the normal lenses. Your wallet will also be off when you start in that direction.
Personally, I have tried several cheapos, have a Canon IIF (cheaper RF compared to leica) and a couple lenses for it. I find the canon (a Leica copy) much less appealing than the Auto S2, Konica C35, or Canonet gL17 (or really any camera). I wear glasses, and looking through a 2.9mm x 1.8mm hole for composing is awful compared to a Nikon F3HP finder or a TLR hood. The Canon IIf feels awesome but its a bottom loader, ick. THe Canon also looks awesome but as soon as I finish a test roll its going to auction. A Leica will feel and look awesomer (I have a friends M2 on loan) but I still don't like using it.
I know that super famous photographers used this style of camera and it holds that romance visually as an object, but it does nothing for me as a user. I say all this so that you dont let GAS lead you to a very expensive camera that you wont like without spending some serious time with a cheap rangefinder.