For mascara, I love the Sephora sampler boxes. They give you about 10 trial size ones that really go a long way. I could use them for easily 6 months if I wanted to but especially since I just got contacts, I've been sticking to the 3 month rule. $45 for a bunch of little ones rather than $25 just for one and you get to experiment with different types. Or I'll buy the little $10 ones at the checkout which is probably more expensive but I'd end up throwing the other ones out anyways.
But ones I've found I like (I don't remember all the names so going off of pictures for some of these):
Benefit Bad Gal and They're Real
Buxom Lash
Tarte Lights, Camera, Lashes!
Too Faced Lash Injection
And I specifically remember not really liking MUFE or Smashbox