One of my friends scored 2380 on the SAT I using only free resources to study from. She's trying to help high-school students cut down on the amount of unnecessary money spent studying for the SATs, so she's started writing a fantasy novel which combines humor with SAT vocabulary words.
It's completely free, and if you memorize the words she's using, it should really help your writing/verbal scores.
Mods, please let me know if this isn't allowed. Thank you!