For the last few years I've tried to buy a new bike tool instead of a new bike part when this urge comes over me. I have a strong preference for VAR over Park Tool, and there are often random ebay dealers with small lots of random VAR items. My apogee was buying the VAR headset cup press for something like $200 below list price two years ago... it really is better than Park Tool's though. I also check craigslist for yard sales and go regularly on the weekends as preventative maintenance. But the desire to buy has declined in the last year since I started spending money on machine tools and shop space.