All the mods that were compiled for that plateform. Since all the modders are required to post their source code, you could compile them yourself if you'd want to. It may take a bit of messing around but you'd probably be able to. You could also try to get someone owning a Mac to compile the mod for you.
You need to download the source files, kinda like the raw ingridients for the exe file. Then using this tutorial you can find out how to compile them.
i just downloaded winebottler and allows me to run the exe files on my mac
Wine & Winetricks www.winehq.org