Last.fm's Tasteometer API lets you retrieve Tasteometer scores for pairs of Users and Artists.
To use the Choreos in this bundle you'll need a Last.fm account. If you don't already have one, you can sign up here. For some Last.fm Choreos, authenticating requests will require you to complete the Auth process described under web application authentication pathhere to get a valid session key. Other Choreos will only require an API Key which you can retrieve by registering your application here.