The Elecraft T1 is a miniature, stand-alone antenna tuner unit that can be used with any low-power HF+6m transceiver. The T1 is available both as a kit or a ready built unit.
Don't forget to check out my pictures of the T1.
The OHR WM-2 QRP wattmeter from Oak Hills Research is simple and easy to build. It measures forward and reflected power from 5 mW to 10 W and is indispensable in a QRP shack.
Be sure to check my pictures of the WM-2!
Various experiments with Arduino boards and related technologies.
Various projects and hacks using the Beaglebone – a low cost, high-expansion and hacker friendly embedded computer module based on the Texas Instrument AM3359 chip. See my Beaglebone photos on Flickr or my Beaglebone videos on YouTube.
Experiments with Gumstix Overo embedded computers.