If you compile modules, you might need the same version of the compiler perl was compiled (if you use the Activestate-binary, I think you need VisualC6

That kind of thinking is what prevented me from trying this in the first place. Do you have any proof that purchasing and using VC6 is any different from using the free VC Toolkit I mention above when compiling using the ActiveState build? (not a rhetorical question, I'd like to know). So far I have not found any modules that don't work with the free version.

Well, with the free nmake you can compile a lot of cpan-modules

Strictly speaking, that isn't true. You can *install* non-XS modules with just nmake.exe but you need a compiler to *compile* XS modules. Nmake.exe comes included in the free SDK mentioned above so there is no need to download it separately. But you're right that nmake.exe by itself is useful for installing non-XS modules for those who don't want to or can't download the the full compiler.