well-biked: I'm sorry that you've had bad experiences with bike thieves. Who exactly is "THEM", though? To quote a rural south-centralian such as yourself: "We have met the enemy and he is us". WE are all in bed with thieves--or have been thieves--even if we won't admit that to ourselves. Just a point of fact to counter your somewhat black & white moral universe. As for being a thief personally, especially of cherished property, that is not something I relish or can ethically support.
As far as I'm concerned, reusing abandoned stuff is a positive virtue, and a social good, for the reasons peripatetic states. We live in a stupid, throw-away society. Foolish people throw good stuff away all the time. my mom and dad found a washer/dryer that was perfectly fine except for a $1 switch. my bro found a fully functional, perfect breadmaker. Guess it's in my genes.
If a bike is in any way secured and functional, then by my lights, that's probably somebody's bike (although at UMd., they finally cut off a bike that had been u-locked to a mall rail for a year.) Bikes I consider to be abandoned are in clearly public spaces (open fields) and/or are non-functional (broken chain stay, missing/tacoed wheels, no chain, etc.)
Anyways, thanks all for the feedback. Posting's up on craig's list, so hopefully somebody gets their bike back, or I get a lot of parts I couldn't normally afford. Win-win situation? I think so.