I'm still looking forward for programmatically generating custom jQuery builds from the download page. We Inertially include the whole build for minor things sometimes. Say I want to just use Events, Selector, or Utilities and Ajax.
True... but by pulling jQuery from Google's CDN for example, you theoretically save page-load time anyway. If multiple sites pull from the same CDN, then it's already cached in the user's browser.
If you aren't aware of Zepto ( http://zeptojs.com/ ), you should check it out -- it exists to serve this purpose.