Resources:

• dictionary.com - they've been a pain in the ass lately with the popups and ad script, but I still use them.
• Merriam-Webster - a good alternative to dictionary.com. Their etymology's not as good though.
• Britannica.com: better for people and places.

Words I Like or Find Interesting:

Hangdog: having a guilty, or downcast/intimidated look on your face

anodyne: Capable of soothing or eliminating pain.

stalking-horse: when hunting, a way to sneak up on prey by hiding behind your horse.

breakfast: to break or end a fast.

synoptic: a general view of the whole. You'll hear synopsis all the time, but never synoptic.

desideratum: something considered necessary or highly desired.

concomitant: occurring or existing concurrently.

coeval: n: of the same period or age; adj: lasting through the same era.

manifest: blatantly obvious; evidence of...

salient: protruding; strikingly conspicuous.

solipsism: the theory that the self is the only reality. I don't care for the theory, but I use this word often.

obsequious: fawning; compliant; servile.

slave: this word comes from Slav (as in Yugoslavia, Czechoslovakia, Slovenia...) because the Romans got their slaves from captured Slavs.

pernicious: causing great harm; destructive.

caterwaul: to cry or screech like a cat in heat; to make a harsh noise.

More fun words:

• cloying
• mealymouthed
• unctuous
• fleeceable
• invertebrate
• milksop
• cosset
• henpeck
• incommode
• fussbudget
• needle
• addled
• interminable
• threadbare
• bluenose
• toadying

A few Greek words that I need to research:
apatheia
nomos
physis
logos
pathos
ethos