trueSpace used to be far from free...before M$ bought it to use with their virtual world thingy it used to retail for around $900.00 so it should have some fairly advanced features. A friend who has used it since ver. 2.0 swears by it as much as at it..LOL. It is still in development IIRC Roman's last comment on it's status that I saw.. ...

 

Once in a while I look around,
I see a sound
and try to write it down
Sometimes they come out very soft
Tinkling light sound
The Sun comes up again