60017 Flatbed Truck, $19.99 for 212 pieces. Maroon and orange pieces, and considering how poorly priced the latest crop of City sets are, this is a godsend.
10662 Lego Creative Bucket, $29.99 for 606 pieces. A nice range of colors with a decent amount of SNOT and Technic bricks.
10657 My First Lego Set, $14.99 for 148 pieces. For a "first" set there are a fair amount of the fiddly bits that we love in here. You can even build on the box lid!
700000 Razcal's Glider, $11.99 for 109 pieces. The price point might be a little off -- $0.11-- but there are a ton of little fiddly bits, and a new piece, that are great for building mechs with. If you can grab it on sale, do.
21013 Big Ben, $29.99 for 346 pieces. Here's a first, an Architecture set being recommended for parts. The secret? It has nine Travis bricks, three 1x1 w/2 Stud bricks, five "new headlight" bricks, and a ton of tan plates and bricks.
76004 Spider-Man: Spider-Cycle Chase, $19.99 for 237 pieces. Two new Technic pieces, Cheese Slopes, Travis bricks, some nice green pieces, some tan, and a PpP of $0.08 for a licensed set? Deal!
60018 Cement Mixer, $19.99 for 221 pieces. A large amount of hinges, clip plates, plates w/handles, brackets, and other fun bits make this another good city set.
70003 Eris' Eagle Interceptor, $34.99 for 348 pieces. Right on the $0.10 Price per piece sweet spot, this one is a little larger than I generally recommend. There are a lot of great parts in neat colors, and it looks like a ship from the old Buck Rogers tv show. Sold!