Zpool is the most profitable:
URL: scrypt.mine.zpool.ca:3433#xnsub
Worker:
Password: c=BTC,d=128000
In terms of "bitcoin per watt", yes.. but if he's looking for LTC specifically, zpool isn't the place to go. the scrypt pool there is mining digibyte & verge primarily.
Maybe but Coinbase can exchange BTC to Litecoin for free and it's money in your pocket whatever it's stored as.
Mining is quite split there:
Doge (scrypt) - 363.5 GH/s
Via (scrypt) - 363.5 GH/s
Myriad (scrypt) - 363.5 GH/s
Ninja scrypt - 213 GH/s
Gulden (scrypt) - 155 GH/s
Linda (scrypt) - 105.4 GH/s
Campus (scrypt) - 94.3 GH/s
Pink (scrypt) - 59.5 GH/s
Digibyte (scrypt) - 41.2 GH/s
Verge (scrypt) - 38.1 GH/s
Litecoin (scrypt) - 32.6 GH/s