So I was trying install the new Opera for Linux which unfortunately is offered in Debian package only... deb2tgz to the rescue! Well that failed miserably since the new .deb also allows for XZ data which isn't supported by deb2tgz. So after some scripting (i.e. more or less completely rewriting it) I managed to repackage Opera into .txz. 

Here's the patch for deb2tgz so it support XZ... it also completely repackages the data and adds a nice little slack-desc description file. It's been tested with Opera and Skype (...) and the initial results look promising... that said, let me know if you have any packages that break.

Fun fact: Opera doesn't really start...