3D Animation software

www.blender.org

Free and Awesome!

 

Blender for free is a good choice however there is a steep learning curve, if you've already into Autodesk/discreet products I would personally recommend Maya PLE (Personal Learning Edition) which is free but renders out with a watermark.

So what are you trying to achieve anyway although 3DS MAX is a 3D application I wouldn't consider Combustion to be one, it's more of a compositing application IMHO.

Combustion you can get on a Mac however I don't think they've released a native Intel version yet, however a good alternative is Motion or After Effects.

 

Hmm, I'd have to agree with mongrol I use it myself, although it's my understanding that the learning curve with blender is just because the interface is so different to other 3D software.

If you're not familiar with any others, then Blender might be a good choice, it's free and has many tutorials and can make production quality output. Having said that all of ezekielrage_99's suggestions of Maya PLE is great, it's a fantastic program.

It really depends on you, try both and see what are up to your liking, with Blender though the sky is the limit you never have to pay anything and it's open source so it's constantly getting improved.

 

That question is impossible to answer without you telling us what it is you're hoping to create.

 

I use Blender a lot, but Blender was also my first and only exposure to 3D Modeling software. It's extremely feature complete and you don't have to worry with licenses (expensive or not).

I would like to try Lightwave 3D perhaps (I'd love to do some Babylon 5/BSG-ish type stuff), but I rather enjoy the thought that my models are open to be used on whatever platform and as many computers as I want.