[elorant]

I’d give it a try if it worked on Windows or Linux. I’m not willing to buy a Mac just to be able to study a language-I could build a Hackintosh but it’s too much trouble for what it’s worth. Most of the languages out there work on any platform. Even C# works on Unices through Mono. But for Apple’s products its always the same story, our way or the highway.

[cdh]

Someone can correct me if I'm wrong, but I believe the language itself can be used on almost any platform with gcc, not just OS X.

[octotoad]

You are correct. GNUstep would be the most well known project to make use of ObjC outside of the Apple world. Also, since it implements the OpenStep API, you could use it to get a basic feel for Mac development without jumping in to the Apple fog.

[Turing_Machine]

You're quite right, though of course you don't get the Cocoa libraries. GNUStep might give something of the same flavor, perhaps.