Not satisfied with your Zune's measly 30GB hard drive? The folks at iPodMods have detailed instructions on replacing it with a 40GB, 60GB, or even 80GB drive.
This "repair guide" includes detailed photos of each step of the Zune's dissection (though not its reassembly), with a special section devoted to replacing the hard drive. According to iPodMods, you can swap in one of Toshiba's Zero Insertion Force drives--which they just happen to sell.
Looks like fairly easy surgery, though you may wonder about spending $240 on an 80GB drive when the Zune itself costs $250. Of course, bragging rights don't come cheap.