Transformers RPG Humble Bundle has a $40 level for physical items and you'd think the RPG would be one of them but nope it's the GM Screen (which I guess is not included in the PDF bundle), Character Journal, and three different dice sets.

Anyway, for $18 you get these PDFs:

Transformers RPG Core Rulebook
Field Guide to Action & Adventure - 290 page sourcebook for doing crossovers with Power Rangers RPG and GI Joe RPG
The Time is Now - 162 page 4-part campaign
Decepticon Directive - 208 page sourcebook
Enigma of Combination - 128 page sourcebook for Combiner characters (e.g. Devastator)
From Yesterday to Today - adventure
Catch a Falling Starscream - adventure
Winner's Cup - adventure
A Beacon of Hope - adventure that comes with the GM Screen but I'm guessing GM Screen PDF is not included in the bundle
Freebie content

Things not included:

GM Screen
Cobra/Con Fusion - GI Joe/Transformers crossover adventure
Enter the Collection - generic adventure suitable for an Renegade Game Studios RPGs
Unnatural Disaster - adventure
Worlds Collide: Battle for the Multiverse - Crossover event designed for three groups, one each of Power Rangers, GI Joe's and Autobots

Transformers uses RGS' Essence20 system which uses d20 + skill die to determine actions.

Frankly not really feeling it but might buy it anyways.