Like any popular game, Angry Birds has spawned clones. These games are often flash-based, and though most aren’t up to par with Angry Birds, they’re a nice diversion for someone who has slaughtered their fill of hogs.

Just one problem – most of these games require an Internet connection. So what are you supposed to do when you’re offline? Let’s have a look at a few indie titles that provide physics-based gameplay but don’t require a constant connection to the mothership.

World of Goo [No longer available]

Did you forget about this game? It was an indie darling a few years back, but has fallen off the face of the earth recently. That’s a shame, because although this game pre-dates Angry Birds, the gameplay and graphical style is similar. Indeed, this is arguably the game that inspired the current breed of physics-based indie titles.

As the title suggests, you’ll spend much of your time playing with Goo. Not just any old goo, however, but rather goo that can be used to construct building and bridges. If you ever tried to make things out of Play-Doh when you were a kid, you’ll know what to expect.

The game starts out easy, but becomes increasingly difficult as the levels challenge you to build more complex structures. Eventually you’ll need to learn to exploit physics to create elaborate solutions, and when things go wrong, it all comes tumbling down in a gooey mess.

World of Goo is available for Windows, Mac, Linux and even the Wii. It is $20 on the developer’s website, but less than $10 on Amazon.

Crush the Castle 2

Available on Armor Games, the flash game site that posts a new game every nano-second, Crush the Castle 2 is almost identical to Angry Birds. Your goal here is to kill pigs – er, nobles – in a castle. You do this by flinging a variety of rocks and bombs at them.

Level design in this game is frankly not as solid as Angry Birds, but it’s better than most clones, and it is supported by a wide variety of ammo types that add spice to the game. Although the goal is to complete your task in as less shots as possible, it’s sometimes more fun to just plow through a castle’s walls with a barrage of bombs.

Now, you might be thinking "wait, isn’t this game web-based?" That’s true, but you can download it and play the flash file on your PC without an Internet connection, although you will need to connect if you want to use any of the game’s online features.

Crazy Machines 1 + 2

The original Crazy Machines was a lot of fun, but it was a bit before its time. Launched in 2005, it received some praise but generally flew under the radar. If it had arrived in 2008, it likely would have been given as much attention as World of Goo.

Now the sequel has launched, but both Crazy Machines titles have similar gameplay. You’re given a series of challenges and some tools to solve them. Usually the tools must be used to knock something over or move an object. Beating the levels requires creative thought and familiarity with the concept of a Rube Goldberg machine.

Both games are available on Amazon’s game site. The original is only $6.51, while the second is $10.99. Do be warned, however, that Crazy Machines 2 is known for its demanding system requirements. If you don’t have a beefy PC, it is unlikely to play smoothly.

Conclusion

There are plenty of games like Angry Birds available, but once you exclude those that can’t be played offline, many of the choices evaporate. If you know of a solid physics-based game can be played without a connection to the web, let us know in the comments!