It's so simple! Or at least this week's installment of the Vault is. We're focusing on simple ideas today, games that do a lot with a little to make you go ooooh. (Whether you add the aaaaah is up to you; no pressure.) Here's just a few of our favourite titles that embody the concept of simplicity... whether it be in style, controls, or gameplay... and serve up a game that manages to clobber your best efforts at productivity.

• Free Rider 2 - Continuing in the oddly compelling vein of Line Rider, this webtoy combines physics with user creativity to deliver the world's most unsafe biking experience. Use the tools at the side of the screen to create a track as gentle or as crazy as you want, and then send your oblivious little biker down it at break-neck speeds that would make mothers everywhere fly to their windows and bawl "Get down from there!" Not only is watching your biker painfully wipe out entertaining, but the toolset practically begs for one-upmanship, for you to call your buddies over to the computer and proudly crow, "Check this out!" as you show off your painstaking recreation of Universal Studios' Hulk Roller Coaster.
• CoBaCoLi - Tonypa has been mastering the art of the fiendishly simple game for years now, and this strategic puzzle game was striking enough to take home the "Best of 2008" award in the simple idea category. The goal sounds easy; hit lines with balls of the same colour to make them disappear without running out of shots. Of course, the tricky bit is that the only ball you can control is a white ball; to get the coloured balls to the lines, you'll have to plot out your angles and even work a little physics mastery. The end result is an elegant and addictive experience that will keep you coming back until you succeed, making it the perfect combination of easy concept and challenging execution.
• Chat Noir - Taro Ito's incredibly stylish little puzzle game about a coy black cat requires more than a little planning on your part. The turn-based gameplay revolves around trying to corral the feline by clicking on spots to turn them dark before he escapes off the edges of the map. Which is probably going to happen, at least once or twice, but Chat Noir is one of those games you can't help but keep coming back to; the level design is random, the visuals are clean and elegant, and while it arguably could do with a snappy skee-bop-diddly-ho! jazz soundtrack, it's still somehow as addictive and relaxing as Solitaire.

While we welcome any comments about this weekly feature here, we do ask that if you need any help with the individual games, please post your questions on that game's review page. Well, what are you waiting for? Get out there and rediscover some awesome!