And of course you can get most Linux stuff to run on a mac. In a pinch, I run virtualbox and Ubuntu or the like.
Also, I think TexShop is the best LaTex editor. I tries some for Windows, and they universally suck, IMHO. I can't believe how much time I wasted trying to use word for technical stuff when I was in school. Learn Latex. I will save you life.
In school I did all my data analysis on a Mac using C and C++. Of course some of it was too much for the Mac, so I telnet to the SGI. I was still able visualize everything in GNUPlot and output on or plotter through my mac. Again, I wasted a lot of time in excel until I learned to use GNUPlot. Later I also did some work using Graphviz.
There are a lot of C++ and general IDE for the Mac. Of course there is Eclipse. If you want an OS with a side of IDE, there is always the old standby EMACS. Actually, I use AquaEmacs for my IDE. learn to use GIT.
What I find most interesting is how powerful modern machines are with respect to the requirements of most research. For instance any physics student should invest in Mathematics. It saved my hide in the numerical methods class. It could probably run well on any mac made within the past three years.
Only caution is that a separate graphic card is recommended if there is a lot of data visualization involved. That means a the high end 15" macbook pro.