Get them something trendy. If they don't like black leather leggings, get them a toned down trend like Gap's plaid shirts.
Make sure they stay warm this winter with a cowl neck scarf.
Help them to be eco-friendly with reusable shopping bags.
For the sister who used to love the X-Files and still loves the sci-fi genre, Star Trek.
Ok, I don't have anything cute to say for this one, but this is just a really funny movie. Someone will love the Hangover.