Does somebody know if it is possible to play Mount and Blade and crpg on a Mac? Because now I can only play in the weekends...
Yes.
Yes it is. You will have difficulties with mouse blocking, though 
And never take advice from someone who has never used a mac who thinks that we still use one-button mouse.
cool, anyone playing on a mac? Or is it as good as unplayable?
Yes I do, and it is easily playable, just as much as on a standard PC. That one-button mouse is a pile of urban-legend rubbish, it is free for a reason, and they sell alternatives for a reason (Unless you are one of those odd people who want to buy a 1700 to 3000 dollar Mac just for the status and never use it for what it is intended, in which case they should have bought a PC).
Use BootCamp to install Windows on your mac, install warband and crpg.
This.
To The OP:Basically, if you have an intel chip (and I assume you do) then it (your mac)should have included a nifty program called
BootCampBootcamp allows you to install any Windows Operating system of your choice of the new ones, so XP SP1, XP SP2, XP SP3 (that I use), Vista (Don't use that) or Windows 7. Bootcamp is also
Free and
Legal.
Then just play it normally.
And for the love of god buy a real mouse, and avoid the "Mighty Mouse" aka the Crapple Mouse. I have a 7 button mouse with my mac, and I highly suggest you buy at least a 5 button one if you have not already (though any self-respecting mac user has already done this).
