thelastripper is an excellent utility, but I found it isn't straight forward to install on both releases of Mint I have used - Mint 9 and Mint 10. Thanks to the efforts of a number of key people it now works. These are the steps I had to take to achieve a successful installation on Mint 10.

Installing thelastripper on Mint10
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Step 1.
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# apt-get install thelastripper

This installs version 1.4.0+dfsg-2 as shown by dpkg -l | grep thelastripper.

Step 2.
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Get mono 2.6.7 from Badger ports and install BEFORE completing step 3.

Badgerports is an Ubuntu repository. In order to use it, you must add it to your Software Sources.

   1.      Click on "System", "Administration", "Software Sources".
   2.      Click on the "Other Software" tab.
   3.      Click on "Add...", and enter the line:

      deb http://badgerports.org lucid main

   4.      Click on "Add Source"
   5.      Click on "Authentication", then on "Import Key File"
   6.      Download this GPG key file, ID 0E1FAD0C, and select it in the "Import Key File" window
   7.      Click on "Close", then "Reload" when the pop-up appears. You're all set!
   8.      As root run 'apt-get update'. The system will be updated with the 2.6.7 versions of the mono libraries

Step 3.
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Download system.zip from http://gonzalo.name/tmp/system.zip
1. # unzip system.zip
2. # cd system
3. # gacutil -i System.dll
 

That's it. All you need now is a lastfm account and you're in business!

Good luck.