» What is a gigapixel photo?

Gigapixel photos are images made up of more than one billion pixels. Your normal digital camera has a few million pixels so a gigapixel photo has more than 100 times the resolution than your normal family photos. This results in a extremely high level of details and you can zoom in to see a lot of details that you miss in the zoomed out version.

» How have you taken these photos?

I made a custom photo rig that takes the photos automatically. You can read about the project here.

» I have great location that you must come and take a gigapixel photo from!

Sounds great, please mail me and I will check it out.

» I'm not an engineer, can I still take these photos?

Yes you can, check out these companies and sites for more info:
Gigapan
Papywizard
Clauss Rodeon

» Any other sites I should check out?

The Gigapixel Article on Wikipedia
A real(!) Gigapixel camera
kolor autopano
Gigapix.no