Humane Society of the United States
ASPCA
PETA
local no-kill shelter
At Thanksgiving and Christmas, we also donate food to a local women's shelter
ITA, Galahad - my former employer was a HUGE United Way pusher (one of the big muckety mucks was on the Board of Directors of United Way). During each year's campaign, they kept track of who donated and in what amount. If you weren't on the donor list, high-level executives would come to your desk to try to coerce you to donate. I refused to give in and, as a result, had to put up with alot of snide comments during the campaigns.
I give from my heart to organizations I believe in - not because someone else tells me to give.