I saw this link over on XDA (amazing what you can find over there but its just so poorly organized) that provides an application to quickly switch fonts (but does require a reboot to apply the changes). The best part about the app is that within the app it gives a preview of all the available fonts from within the application, which makes switching to a different font very easy.
[MOD] Font Changer v1.2 (16/09) - xda-developers
I hope you guys enjoy this. Confirmed working on my D1.