JS Fiddle — an online editor for snippets build from HTML, CSS and JavaScript. The code can then be shared with others, embedded on a blog, etc. (via Darren Wood)
SideStep — Mac OS X program that automatically routes connections through a secure proxy when you’re on an unsecured wifi network. (via Gina Trapani)
Junkyard Jumbotron (MIT) — lets you take a bunch of random displays and instantly stitch them together into a large, virtual display, simply by taking a photograph of them. It works with laptops, smartphones, tablets — anything that runs a web browser. It also highlights a new way of connecting a large number of heterogenous devices to each other in the field, on an ad-hoc basis.