If last year's Dirt Rally was too realistic for you, Dirt Showdown is a nice, arcade-y alternative. With its focus on crashing into things for fun, it's a far cry from Dirt Rally's unforgiving and, frankly quite pedantic, must-stay-on-the-road policy. Even if that doesn't sound like your bag, you might as well grab a copy, because the Humble Store is currently giving it away for free.
There aren't really any catches: you simply head to the page and click the glorious "get it free" button. The deal is available for another day or so, but to be safe you should probably grab it now. Phil Savage liked it when he reviewed it back in 2012, writing that it's "the most schizophrenic Dirt to date".
It's not all you get. If the Humble Monthly subscription service appeals to you, you'll also get a 10% discount to sign up for it. The subscription rewards you with a load of games every month, and it's usually well worth the monthly fee of $12. For example, this month XCOM 2 is included.