I was just perusing Steam's current sales and notices the following.
Morpholis $0.24 (9 5% off) http://store.steampowered.com/app/314020?snr=1_8_4__501
BloodRayne 1, 2 & Betrayal each $2 (80% off) http://store.steampowered.com/search/?snr=1_7_7_weeklongdeal…
Penny Arcade's On the Rain Slick Precipice of Darkness each $0.39 (92% off) http://store.steampowered.com/app/213030/?snr=1_7_7_151_150_…
and http://store.steampowered.com/app/213030/?snr=1_7_7_151_150_…
80% off older GTA titles (NB Vice City and San Andreas have had some content cut recently) http://store.steampowered.com/search/?snr=1_7_7_151_12&term=…
Imperial Glory 50 cents (90% off) http://store.steampowered.com/app/277450/?snr=1_7_7_weeklong…
I was looking at some of these too, all of which have Trading Cards.
Saved the best one for last :)
Robotex, $0.19, Trading Cards, Mostly Negative reviews
Morphopolis, $0.24, Trading Cards, Achievements, Very Positive reviews
Woodle Tree Adventures, $0.38, Trading Cards, Achievements, Mixed reviews
Penny Arcade's On the Rain-Slick Precipice of Darkness 4, $0.39, Trading Cards, Very Positive reviews
Cthulhu Saves the World, $0.44, Trading Cards, Very Positive reviews
Dead Bits, $0.49, Trading Cards, Mixed reviews
Ampuatea, $0.49, Trading Cards, Achievements, Mixed reviews
GEARCRACK Arena, $0.74, Trading Cards, Mixed reviews
Postal 2 Complete, $0.99, Trading Cards, Achievements, Overwhelmingly Positive reviews
Zombie Tycoon 2: Brainhov's Revenge, $0.99, Trading Cards, Achievements, Mixed reviews
Deadlings - Rotten Edition, $0.99, Trading Cards, Achievements, Very Positive reviews
Shiny The Firefly, $0.99, Trading Cards, Achievements, Mixed reviews
Kairo, $0.99, Trading Cards, Achievements, Mostly Positive reviews
Dino D-Day, $0.99, Trading Cards, Achievements, Very Positive reviews
The Waste Land, $0.99, Trading Cards, Achievements, Mixed reviews
Echelon, $0.99, Trading Cards, Mixed reviews
&
The Elder Scrolls V: Skyrim, $3.50 (roughly), Trading Cards, Achievements, Overwhelmingly Positive
Would have added some more but it's 0355 and I'm humped - my eyes feel like they've got pins in them.