These are addons that I've built and are available on the Statamic addon store.
SVG is an addon that lets you easily output and manipulate SVGs (unsurprisingly) in Statamic. You can easily inject classes, set the height and width, and add a11y information to SVGs without needing to manually edit them.
Mix allows you to leverage the power of Laravel Mix's version functionality in your Statamic site. This means you can use Laravel Mix's in-build cache busting functionality out of the box. You might still have 99 problems, but a client still seeing the old version of the site won't be one.
These are addons that are either still being worked on, or were built for a specific purpose and won't be released publically. If you're interested in one of these, reach out to me over Twitter.
An addon that allows you to output calendar invites in the four major formats (ICS, Google, Yahoo, and WebOutlook).
Integrate Pardot into your Statamic site, initialise the tracking cookie, and hook in Statamic forms so you can automatically send on contact forms to your Pardot account.