I'm really excited about today's (beta) release of google gears for safari. Why? because, as I've just tested, but enabling the plugin for safari it makes it available for all of my fluid app Site Specific Browsers (SSB's).
If you pay close attention here, you'll know that I'm a big fan of fluid and the idea of SSB's in general. I use apps for Remember the Milk (my current task management / GTD tool) and Google Reader extensively. Both of these sites support gears already for use offline (read: on airplanes). However, by using Fluid (based on Safari's webkit), I had to forgo gears/offline access. Thus, when traveling, I'd taken to opening a tab in firefox for each of those sites (if I remembered, and as long as I didn't need to otherwise restart firefox, etc).
Well, I just had a wonderful experience. I downloaded gears for safari, installed it... and instantly all of my fluid instances were gears enabled. Love it!