I've been here a few months, pretty silent :-[ but totally enjoying this thread especially. Just wanted to chip in something I use. Not quite as powerful as MyBase and the likes but it works for me. My conditions are:

Must work on both PC and MAC
Must be portable
Free is nice but not a requirement

I ended up with a Firefox Plugin. It seems natural to me since I have FF running 99.99% of the time. The plugin is called Scrapbook - http://amb.vis.ne.jp/mozilla/scrapbook/