On Win32, Gimp is relocatable. It can find out it's own path at runtime and find
out where it's data files are. On Linux, all paths in Gimp are hardcoded at
compile time. This means the app is not relocatable.

I work for the autopackage project (http://autopackage.org/), a new installation
system for Linux. One of the features of autopackage is that packages can be
installed to any prefix (although that's not recommended), which means the
software must be relocatable. I'm currently maintaing the Gimp package (mainly
for testing purposes) and it is important that Gimp is relocatable.

I modified Gimp to make it relocatable on Linux. It utilizes a special version
on BinReloc: http://autopackage.org/docs/binreloc/
This relocability on Linux support does not harm portability because it's
autodetect in configure.
Here's a patch against 2.0.0. It's mostly finished (though not 100%). I'd like
this patch to be reviewed.