Dan Stahlke's web page
Software:
SwathViewer
GDAL scripts
Gnuplot iostream interface
scopemm - plotting library for gtkmm
FFTW/Blitz++ interface
lxt - an Xtree clone for linux
Java fractal generator
Electronics:
22-bit voltmeter using AD7714
Power usage logger
AVR-USB temperature probe
AVR digital comb filter (humnuller)
Driver for Nokia 6100 LCD
Cell phone privacy modification
Inside the PayPal security card
Universal Sensor Amplifier
Misc:
Physics papers
Links:
commandlinefu.com
If you use the Unix command line, this is definitely worth checking out
Bill Beaty's Science Hobbyist
Lots of amateur science stuff
AVR Freaks
The availability of this resource was the reason I got back into microcontrollers
Techlib
Information on home-made VLF/ELF receivers
Electric Field Disturbance Monitor
This circuit can detect movement from across the room by monitoring changes in the ambient electric field
I want sparks & I want them NOW!
Simple high-voltage Marx generators
perl -e 'print "P1\n256 256\n", map {$_&($_>>8)&&1} (0..0xffff)' | display