Cartoon software?
 

Is there any, really working, software for making cartoons/animations?
I have heard that gimp would be one, but I can't figure out how it could save mpeg/avi.
I don't necessarily need any flash-kind features (vectors,tweening,etc), but onion-skin would be nice.

O! I DO know of one that is for animation and drawing for cartoons. I was researching different 3d modeling software and I stumbled upon that, but I forgot the name. I will do my search on that software again once I get back from work, I'm sure you will be pleased. And yes its for linux. (Native! :D)

I found this http://www.synfig.com/, but I do not think it is the software I saw before, but seems to be better or the same. Hope you like!

Here a list of some I heard about:
Wings3D: www.wings3d.com
Blender: blender.org
k3d: k3d.sourceforge.net
yafray: www.yafray.org
toxic: www.toxicengine.org
aqsis: www.aqsis.org
pov ray: povray.org
jahshaka: www.jahshaka.org
cinelerra: heroinewarrior.com/cinelerra.php3

good luck !

Blender is a nice tool, once you learn how to use it (haven't worked with it much myself, but have seen some things a friend has done with it. Versatile, very powerful.) I think it was actually developed by Silicon Graphics (the Hollywood special effects company) http://www.blender.nl/

I've also found these:
K-3D http://www.k-3d.com/
Behemot: http://www.behemot.com/

Hope you find one you like!

You two misunderstood me, I meant 2d-animation software. I'm mainly looking for tool for frame-by-frame animating, but also something like Macromedia Flash could do it. And I forgot to say that it must be free at least for non-commercial use.

Synfig would be very good, but I can't get it working and it is just developer's preview, so I don't think it would work too well. KToon is second good, but highly under-development program, it doesn't even have undo yet.

I just found CinePaint, it looks like Gimp with more video features. I have today no time to test it. Tomorrow I'll be back and tell you what it really feel like.

Cinepaint wasn't even good as gimp, its created for editing videos.

Now I managed to compile and install Synfig, but only video-format that works is .gif.
But still it is best I have found, so I'll play around with it until I found better.

I noticed with Synfig that vectors isn't my best area, so what I really need is regular frame-by-frame software.
(If you don't understand what I mean for frame-by-frame, it is like making gif-animations.)