Linux Learning Idea!

Originally Posted by Rothen 

Learn to do everything in the terminal. There's a lot of mundane tasks that we do in a GUI but can also be done easily in the terminal, most of the times faster. What might be fun is to install a tiling window manager like xmonad and just dig right into some serious terminal work. Also you can try to learn Vi, Vim or Emacs which are text editors for experts. I haven't really even used them much and instead I use nano .
Bonus: Learn how to play Dwarf Fortress

Originally Posted by TurboTurtle 

Recompile your kernel, using the latest stable release. Through research, eliminate as much "bloat" as you can, so that you have everything you need for your specific hardware configuration but don't have an enormous kernel.
The recompiling process itself is very simple, and Transhour has an excellent guide here under the How-To section. The key to this project is learning just how extensive the kernel is, and how much is built into it by default that you probably don't need.
Key factors to keep in mind:
1)Read the help menus for each kernel item. If you are using menuconfig (you'll see this through Transhour's guide) press 'H' to see these menus for each line item. If you use xconfig for kernel configuration, it will be displayed in a dedicated pane for each line item.
2)Compile for your specific CPU architecture. Note, there are multiple ways to ensure this, not just through menuconfig/xconfig. Again, pay attention to Transhour's guide.
3)Unless it's a very specific hardware item (I.E. "Support for 3ware RAID controllers" and you don't have one) if you are unsure about an item - Google it. If you're still unsure, leave it at the default. Some kernel options may not be very obvious in their effect at first. However, if you just go disabling everything you'll most likely have a non-functioning kernel.
4) Remember, if you get a non-working kernel it's not a problem. Just reboot and use the previous kernel (when you boot to GRUB each kernel will (read: should) have a separate entry). Recompiling a new kernel has zero affect on other kernels.
5)Do not delete your default kernel. Many people will delete the default one once they have recompiled a new one (even without testing the new one). Even through multiple kernel compiles/patches/etc.. I always keep the default (that is, the original one from install time) kernel available as a just-in-case-something-nasty-happens fallback.

Originally Posted by Plan9 

oh wow, that's a harsh first challenge. I'd have opened with something a little more n00b friendly.
Still, I guess you have to start somewhere.