First up, Turborilla's Mad Skill Motocross. For a game with only five controls, MSM turns out to be a hell of a lot of fun. On the surface, it's a simple physics-based 2D motocross motorcycle racer, but below the hood there's some tricky finesse required to pull off the win.

First of all, the controls are: up arrow key -- accelerator; down arrow key -- brake; left arrow key -- pull back on handlebars; right arrow key -- push forward on handlebars; space key -- special. What's meant by "special" we'll get to in a bit.

For each race, you're dropped unceremoniously from the sky onto the track, where you have to wait for the green light to ignite to get started. It is possible to jump the gun, however, and you'll lose points for that. Past that, not every race will be against an opponent; sometimes you're just trying to beat the standard time. Whichever it is, however, there is a specific mechanic that you must master, and it's more tricky than it sounds.

Essentially, you can keep the accelerator constantly depressed; in fact, you kind of have to, just to make the time. You'll rarely, if ever, touch the brake. For this game, it's all about the tilting. See, the track bears any number of bumps and ramps on itself, for varying degrees of height. Sometimes these will send you flying to great heights, sometimes they'll elevate you just enough to throw off your orientation. No matter what happens, success demands that you land properly.

For example: if you're tossed way up in the air, you have some degree of rotation. If you notice that you're about to land on your front tire first, you need to pull back on the handlebars to correct that, or you'll hit the track in such a way that you'll be pitched immediately forward, breaking your neck -- which provides a great snapping sound, and groaning from your broken body. This happens quite a lot, actually, so get used to it.

The problem is that it's difficult to get the feel for how the rotation instantiates. Holding either key down keeps the rotation going at an even rate, but sometimes it seems like there's a lag, so it's easy to misjudge the stopping point. It's easy to overshoot a good flip, and you won't always know until the split-second before you land.

As you play, each succeeding track asks more of you. You get more points for performing mid-air tricks like backflips, double backflips, frontflips, catching a lot of air, etc. The way to pull these off is to know precisely how much time you have to execute each, and start doing them the second you take off from a jump.

Pulling out the win in time-based challenges is all about getting that back tire -- the once that provides the actual acceleration -- down safely as quickly as possible. So even tiny take-offs into the air can mean disaster if you're not on the ball enough to correct orientation mid-flight.

All in all, Mad Skills Motocross has a lot to offer, and it's far more challenging than you might expect. Definitely worth the download.