I saw this one today, 40031 Bunny & Chick polybag
. While there are some "enh" parts in the set, it has four Travis Bricks, two Headlight bricks, and some other good parts. It also has 52 pieces and retails for $4.99 USD, which means it falls into the $0.10 per part range which is right in the sweet spot. Also, it's a seasonal item so, if it stays past Easter it'll probably get marked down.
Another one that's good, but not in my usual price range for recommendation, is the 5767 Cool Cruiser
. It has all the usual fiddly bits we love but, the thing that knocked my socks off was the two Trans-Clear Headlight bricks.
I almost forgot this one, 7977 Seabed Strider
can be turned into three simple mechs.
As can be seen here.Photo Sep 11, 7 10 01 PM
by Cid Kraken
, on Flickr.