title: URL-Compact representation of GUID/UUID?
body: <p>I need to generate a GUID and save it via a string representation. The string representation should be as short as possible as it will be used as part of an already-long URL string.</p>
  
  <p>Right now, instead of using the normal abcd-efgh-... representation, I use the raw bytes generated and base64-encode them instead, which results in a somewhat shorter string.</p>
  
  <p><strong>But is it possible to make it even shorter?</strong></p>
  
  <p>I'm OK with losing some degree of uniqueness and keeping a counter, but scanning all existing keys is not an option. Suggestions?</p>