I'm the developer of Universe Sandbox. Thanks for the mention Beta.
http://universesandbox.com/I buy Sandbox 1 but a week later Sandbox 2 came out and then Sandbox 1 was no longer supported.
;-;
Everyone that bought Universe Sandbox 1 for more than $20 within a few months of the release of version 2 (May 1, 2010) got a product key for version 2 as well. And I still offer version 1 for download. When did you buy and for how much? (As version 1 was name your own price)
If you bought version 1, I'm happy to offer you a product key for version 2 for whatever price you think is fair (the same deal as version 1, however this offer is only available to those that purchased version 1).
... PROCEDURAL GENERATION CAN DO ANYTHING
There's some truth there, but doing awesome things takes time. And the finite nature of time is why I charge for Universe Sandbox.
already tried it and it sucks because it costs money
Selling Universe Sandbox is how I make my living. The sales of Universe Sandbox are why I've been able to dedicate the last year to development full time and why it's the best graphical gravity simulator available. And I think the current price is very affordable at $19.99.
And back on topic... The Space Engine is super cool. It's very impressive. I wish Universe Sandbox had some of its capabilities.