StackExchange-style "related tags" block using drupal views? StackExchange sites, and various other site around the 'net, have a nice tag drill-down feature: You can go to a tag page, like https://drupal.stackexchange.com/questions/tagged/views, and then you can select tags from the "related tags" block, and you are sent to a page that filters contents on the union of the two tags. You can do this as many times as you want, and you end up with only content that has all of the tags you've selected. The tags in the "related tags" block are sorted by popularity, and list the number of items tagged.

Is it possible to do this in drupal? How would one go about this? I'm imagining something like a content-view for the tag page, filtered by tags; and then a taxonomy-view for the block, filtered by relationships with contents in the first view. Seems like a bit of a complex mission. Is there a simpler way?
There's a module that I believe does what you want: Similar by Terms


  This Drupal module attempts to provide context for content items by
  displaying a block with links to other similar content. Similarity is
  based on the taxonomy terms assigned to content. Blocks are available
  based on similarity within each of the defined vocabularies for a site
  as well as a block for similarity within all vocabularies.