Snag It (PC)
http://www.techsmith.com - this program offers more than 40 ways to capture images, text, Web content and onscreen activities. It also has an easy-to-use graphic tool that lets you add text, callouts, arrows and highlights to your captures.
Snap'n Clip (Mac)
http://www.pixture.com/mac-snc.php -this
is software that allows you to take clippings from pictures
and store them as thumbnails. Within the software, there
are a couple other options that you can use. One of these
options lets you copy from the screen and the other lets
you take pictures.
Clip2gif-freeware
for converting pict files to gif files (Mac)
Image
editors for PC (some free)
Recommended by Keith- Irfanviewer-PC
image editor ("I discovered that IRFANVIEW, one
of my recommendations for image viewing and editing, now
INCLUDES a simple screen capture action. This is great because
it can save directly to GIF or JPG or any of the other common
formats. Although IRFANVIEW can do SELECTIVE screen captures,
once you do a window capture you can crop it directly in
IRFANVIEW before saving.")
ScreenSeize (PC)
http://www.pcmag.com/article2/0,4149,22140,00.asp -this
is what Keith Amano uses :) He says it can do a variety of
capture types, has hotkeys, and also let's you choose to
leave the cursor in or out of the capture. Best of all it's
free.