I'm not sure why (or how) but Keegan has been sending me the absolute motherload of pre-made Javascript packages and they're all worth checking out and bookmarking for future needs.

• Isotope - very robust layout and filtering scripts.. similar to Masonry (same developer involved) but seems to be more.
• jQuery Waypoints - very simple way to integrate Infinite Scrolling, Sticky Elements, Scroll Analytics and Dial Controls. Absolutely love the Sticky Elements option.. this one goes in the bookmarks fer sure.
• Modal Alternative - at this point a modal shouldn't be all that difficult but I'd love to see some standardization across the web. I'm not sure if this is the script to do it but it's a rather sleek solution.
• Simple Tooltips - tooltips are built into the browser so I often don't bother with scripts like this but, occasionally, it can be very nice to have a little extra info. It's tasteful and the tech has come a long way since the initial release of jQuery.