* Before restoring files, we should check that there is sufficient disk space
  to restore the files.

* Do not always rewind the tape after every operation.  It's time consuming.

* Progress meter for converting old tape indexes to the new format.

* Better estimates of backup sizes (especially incrementals).  Look at the
  source code for tar.

* Send in diffs for ktreeview code to Johannes Sixt.

* Put the tape block size in the tape header file.

* Port to Solaris/AIX/etc.

* Include information about each archive in an archive header.
  Include things like block size used, backup profile information,
  etc...

* While backing up files, write the index to disk directly instead of
  keeping the entire index in memory.

* Better error checking for read/write access to the tape device.

* Log tar error messages (maybe instead of file names).