The best replacement for second life is imvu.

The best alternatives to second life are rated as following:
★★★★★  imvu
★★★  sims
★★★  entropia
★★  there
★★  real life
★  opensim
★  entropia universe
★  red light center
★  minecraft
★  inworldz
★  sims 3
★  kitely
★  kaneva
★  onverse
★  utherverse
★  openlife
  playstation home
  imvu better

Your alternative for second life is not listed? Suggest!
Speaking about second life, one probably shouldn't forget about poser.

Other search terms related to second life and their ratings are:
★★★★★ poser
You have in mind a companion for second life and it is not yet here? Propose!



Google Trends

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second life
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