Books mostly. Some from movies. If I hear or see a name I like I usually search it up and write it down. Some crabs did already have names when they came to me too. These three names I just love, though I did read a series where the main character was named Aisling (Aisling Grey). Salma Hayek...need I say more.

Aoife I just happened across while searching for names. My favorite name site is behindthename.com.
The crabs still with me today....
Collins is after a football player, Nick Collins.
Elanor, Niphredil, Athelas, and Taniquelasse (Tani) are all plants from Middle Earth (Lord of the Rings).
Cinnamon and Rameriz are just random names some of my boys picked.
Chunk is from the Goonies.
Algaliarept is from the Hollows series (aka Rachel Morgan series).
Lettie is from Howl's Moving Castle.
Dola is from Castle in the Sky.
Emerald, Montana, Cannonball, and Popcorn were already named when I adopted them.
I could very happily list all the crabs I've had but I don't want to bore you. Some were within the themes listed above. A few were from the Inheritance books.