Things on this page are probably dead or at very best unmaintained and dangerous, but they worked once and it's nice to remember things sometimes.
Shelf was an app for MacOS that looked at the current foreground application using Apple Events, and tries to figure out if what you’re looking at corresponds to a person in your Address Book. Then it’ll tell you things about them in a floating window. So open a chat conversation with someone in iMessage and you'd see a list of recent emails and tweets by them, links to their homepage, the local time in their timezone, this sort of thing.
Alas, recent mac app sandboxing rules have made it clear that Shelf in its current form is dead.
A collection of scripts for tracking unread count (I'm musing other things, though) across various online services that I use, so I can easily see how swamped I am with data this week.
Made Atom feeds out of things that didn't have feeds, because I like having feeds. Basically, I got bored of having to jab at 5 icons on my phone every time I wanted to do a sweep of "what my friends are doing" - I'd much rather just subscribe to feeds and my RSS reader can tell me about things.
DjangoKit is a framework that will take a Django application, and turn it into a stand-alone MacOS application with a local database and media files. It started as more of a thought experiment than an effort at producing a real application, but I have it working, and you can package perfectly usable stand-alone applications with it.
Generated a new flickr set in your account containing a list of the photos that other people had liked the most, based off your Flickr stats. Flickr (effectively) killed their photo stats in early 2013, making this useless.
Instagram gives you a single, very very simple, view on the photos of your friends - a flat list in upload order. This is a quick hack that emulates a similar thing for your flickr photostream - just stuff your contacts have uploaded, in order. Formatted for iPhone.
A stand-alone ruby/webrick server that will expose a Jekyll source folder via the Blogger / MT / Wordpress XML-RPC metaweblog interface, allowing you to create/edit/delete posts and pages using a GUI client, such as Marsedit.
This might still work. No real reason why it wouldn't.
A (read-only) simplenote client written in html for mobile devices. Intended mainly so that I can read my simplenote notes on my android phone, but it should work on most clients with a decent browser. Uses HTML5 local storage to cache note bodies, and syncs things properly, so might even work offline.
Not listed here:
Interminable Perl modules, best left forgotten.