Remember those old Java physics applets that let you mix water, sand, and various other materials together, with gravity and "realistic" physics being the desired end result? I used to spend hours playing around with those. Back when physics in games was a relatively simple affair and damage models were a novelty, the freedom to just play around with materials was exciting.

Fast forward to 2013, and we've got ultra-realistic ragdoll physics, volumetric blood and gore and dynamic lighting that can bring any dull and boring scene to life. We've also got a whole new league of physics sandbox simulations – beautiful 3D worlds, level editors and stupidly realistic damage.

Here are 3 of my favourites, as well as a newcomer that's set to change the way you think of driving simulators.

BeamNG DRIVE [No Longer Available]

BeamNG DRIVE is a physics simulation like no other. Currently it's in the alpha stages of development (that's one stage before "very not ready" for the uninitiated) but it still manages to knock the socks off of anything else out there. The "game" currently costs $15 for the pre-release edition, which means a guaranteed upgrade to the full edition when it's released, but you can also download the tech demo for free [Broken URL Removed] to try it out first.

http://www.youtube.com/watch?v=X77cThD4vj8

Essentially, BeamNG DRIVE is a soft-body physics sandbox running on Crytek's CryEngine 3 (as per Crysis 3), which is technical speak for "holy crap look at that damage model!". The alpha comes pre-loaded with 5 fully destructible vehicles, 6 terrains to explore and modify and the keys to the modding tools. 

As a Mac user, I'm spitting teeth over the part of the FAQ that says "Currently we only focus on the PC platform and we cannot say if or when we will support Mac" and Linux users will be equally disappointed. The fault here lies more with Crytek, who have yet to port their engine to any platform other than Windows.

http://www.youtube.com/watch?v=hVsm7rFZwH0

Regardless, Windows users should be frothing at the mouth at this point, particularly as the team intend to add a whole host of "game" extras to their creation including destruction derbies (how could you not?) and police chases. Even if you can't play it right now, check out the LazyGameReviews preview above for a detailed look at the future of video game physics.

Rigs of Rods

Before the BeamNG DRIVE developers started work on their current project in 2011, they had another baby in development called Rigs of Rods. We've featured the app before in 2010, and never again since. This is because the development appears to have ceased on Rigs of Rods so that BeamNG DRIVE can carry on the tradition. While BeamNG DRIVE is built with car-on-car collisions in mind, Rigs of Rods certainly wasn't.

http://www.youtube.com/watch?v=3A6OHnAD_Pc

The game is open source and cross platform, though the Windows version received the most work (with Linux and Mac versions also getting a look in, albeit with considerably less polish). All versions were built with a soft-body sandbox simulation in mind though, and vehicles react according to their construction, weight, suspension and collisions.

While the game was initially designed to accommodate trucks – Over The Top style – the game received an incredible amount of additional content from both the developers and community members. These include cars, a monster truck, cranes (that can actually lift things), off-road buggies, helicopters and planes. All for free.

http://www.youtube.com/watch?v=bQkWQmethEY

Sure, it looks like an unfinished three-year old game that's not been touched for a while, and that's probably because it is. It will crash, and glitch, and things will go very wrong, but it's still an unbeatable experience for free.

Garry's Mod

An absolute work of art, Garry's Mod has received so many updates and extras over the years you'll be forgiven for not recognising it if you haven't played for a while. Using Valve's Source engine, Garry's Mod is a Half-Life 2 mod which means that it requires a copy of a Half-Life 2 powered game (like Half-Life 2 or Counter-Strike: Source) and the exchange of 10 measly dollars.

http://www.youtube.com/watch?v=z_Y0Wf7HWAI

For you money you get unfettered access to a huge range of Source engine resources including models, weapons and the legendary Garry's Mod toolbox for constructing weird and wonderful creations. The whole thing can be taken online, either as a co-op experience with friends, or as a rather chaotic public server experience.

What makes Garry's Mod special is its versatility and near-infinite applications. Not only is it just plain fun to play around with physics objects like rocket boosters, weights, ropes, axles and wheels but there is also a creative side behind it. Many have used Garry's Mod to create Rube Goldberg machines, comic strips and even whole web series.

http://www.youtube.com/watch?&v=OHxyZaZlaOs

Above you can find Half-Life: Full-Life Consequences, a piece of poorly worded fan-fiction brought to life with thanks to Garry's Mod and some excellent voice acting.

Have Fun

BeamNG DRIVE is arguably the most exciting of the bunch right now, and for my money it's the best use of the Crytek 3 engine we've seen so far. I've also spent way too many hilarious nights sliding down mountains in rocket-propelled bathtubs not to heartily recommend you all purchase a copy of Garry's Mod too. The best thing about these simulations is the level of freedom you're given. They won't appeal to everyone, but if you're the sort of person who is always tinkering and pushing your existing games to the limit, these titles will be right up your alley.

Do you have any other favourite sandbox games we should take a look at? Leave your thoughts in the comments below.