I've owned only a few gems and a load of cheapskate tat, but my top 5 is as follows:
1. Gibson G-3 (never being sold, ever)
2. G&L Tribute L-2000 (despite a difficult start I'm really digging this one now and I can't see the point in getting a USA model)
3. Epiphone Les Paul (Not So) Standard (so much work gone in - EMGed to death, selector switch added)
4. Traben Chaos Attack (nice enough bass, light, well made, good sound, recorded with it, but ultimately didn't have that special attachment to it)
5. Fecker Imprecision (cobbled together Squier, Fender, Seymour Duncan, Badass - notable for having the lowest non buzzing action I ever achieved on a bass)