Re: A mac?
Check this site and chose your categories.
e.g. I use VirtualBox, the one for virtual machines (to get WinXP, Debian, FreeBSD running on it)
There is a port of OpenOffice for Mac.
For MindMaping you could use openmind.
For browser you could use now FireFox (I never use Safari).
And there are other hordes of free utilities. Its all your choice.