A game I have been spending way too much time on these days , wanted to post much earlier but I wanted to get a suitable screenshot first, took a while getting there
I think you will agree its worth the wait
Title: Kerbal Space Program (Early access - Alpha , still in development phase )
What is it ?
In brief its a sort of serious space program simulation but at the same time is not too serious and has comical elements to take away the serious business aspect of simulations.
At the moment there is no mission or task for the players (coming soon) so the player just messes around with unlimited funding and all the parts immediately available for use as you see fit.
What can you do ?
Build and launch rockets, orbit the planet of Kerbin, put up space stations in orbit, dock with stations in orbit, fly to the Mun (moon), fly to other planets in the Kerbol System, build spaceplanes (and try get them to orbit or dock with stations)... with just the stock game (none modded), but mods then add more stuff to keep you busy.
Some mods add a whole new resource you can scan for and detect on planets and moons, which you can then mine for and turn into fuel to power your space program (getting a Kethane mining operation going on the Mun can supply fuel much easier than laboriously hauling it out of the dense atmosphere and heavy gravity of Kerbin ).
Mods add ability to scan planets for height maps and other data, others add life support requirements, change atmosphere behaviour for planes, add airships (big balloons), add robotic arms and servos, more parts to make your rocket / plane more pleasing to the eye, space station parts, base parts to make bases on the Mun or even other planets... and more, the mod scene is absolutely bustling.
It does rely on you to use your imagination to provide goals and missions at this stage.
How is the game ?
Currently it is playable and fun but has serious issues, is resource intensive and can make the toughest CPU's cry if your projects get too large. There is also issues with odd behaviour, and physics going mad (quicksave is your friend).
Graphically its not bad but pop in is common, textures show seams, laggy animation at times. The game can have some awesome screen shot moments and isnt ugly.
Sound is pretty limited to dull music and to engine noises, some effects like explosions and stage decoupling but not much on the audio front, not really a bad thing.
Controlwise the game plays best on a Mouse and Keyboard, Flight stick and gamepad support is sketchty at the moment.
Is it fun ?
Yes and no. It can eat up hours of your time happily designing all sorts of stuff, but can also provide a lot of frustration when things dont work and some current limitations on the building aspect of the game prevent some ideas, or physics play up and cause issues with your designs (most of the time in heavy gravity areas like the home planet Kerbin).
It is challenging (without cheating or getting mods to do the hard parts) to master aspects of designing and piloting, docking alone is a sod to get to grips with and is a slow and careful procedure, but VERY satisfying when you get it right... that first landing on the Mun is surprisingly intense for such a title.
Should I buy it ?
If you enjoy tackling a game that is challenging but open in scope and lets your imagination loose, if you are happy to set your own goals and limits, and have a lot of patience (space isnt all that exciting, mostly bursts of tension with a lot of mundane and a sudden dollop of satisfaction in achievement)... yes, it isnt even that expensive but offers literally hours of potential entertainment... and the game isnt even finished, lots still to come.
I wouldnt get this game if you dont have much time, or if you dont enjoy open ended games and prefer quick bouts of fun.
It doesnt have any Multiplayer, or plans for Multiplayer and wont add weapons or alien races (other than the Kerbils).
It is closer to a simulation than a arcade game, and as such does require some learning and researching on your part.
The game is also prone to odd issues and crashes (though my experience has been crash free, just some odd physics behaviour and occasionally a craft design will get messed up when moving from the Vehicle Assembly Building to the Launch Pad... messing up the craft save file).
I personally am enjoying it, despite the bouts of frustration, the sheer scope of the title is enough to keep me busy for a long time... and then there is the mods to explore.
Worth the price and there is a very OLD demo available at the homepage (IIRC).