W4RNL on Antennas (a great reference I go back to time and again)

Great-circle maps (WM7D, NA3T and NV3Z team up to give you custom maps online; not just for DXers)

Going mobile? You need to see K0BG's comprehensive on-line resource!

NVIS Global Propagation Map - updated hourly

E-Ham reviews - gear evaluated by hams, conveniently categorized and summarized

QRZ.COM - a fast way to find names,callsigns, hams in an area and more.

FEMA Independent-Study Courses - learn the basics of ICS and NIMS for free!