The best replacement for thin client is zero client.

The best alternatives to thin client are rated as following:
★★★★★  zero client
★★★★★  fat client
★★★★★  thick client
★★  vdi
★★  rich client
★★  dumb terminal
★  client server
  ncomputing
  virtual desktop
  desktop pc
  diskless
  network computer

Your alternative for thin client is not listed? Suggest!
Speaking about thin client, one probably shouldn't forget about vmware view.

Other search terms related to thin client and their ratings are:
★★★★★ vmware view
You have in mind a companion for thin client and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of thin client in all years. Click on graph for more.
thin client
zero client
fat client