KaMaKaZi_KiNg

hey. i wanna run windows and mac os x on my comp. Is there any way that i can dual boot it. I just watched ep 2 again and it looks cool and pretty easy. But i dont wanna have to go out and buy another HDD to install OS X onto when i wont be using it that much. can anyone here help me out? i dont know much about linux so if u can help please keep it simple. Thanx