title: Which collection for storing unique strings?
body: <p>I'm looking for a collection just like <code>Dictionary(OF Key, Value)</code> but I don't actually need a key and value. Key itself is enough. So something like <code>Collection(Key)</code>. It shouldn't accept duplicate keys.</p>
  
  <p>I've looked up couple of collections in .NET Framework but couldn't find what I want. Currently I'm abusing <code>Dictionary(OF String, String)</code> and setting Value as <code>Nothing</code> all the time.</p>
  
  <p>Shall I just continue abusing Dictionary(OF T,T)?</p>