The best replacement for time machine is time capsule.

The best alternatives to time machine are rated as following:
★★★★★  time capsule
★★★★  superduper
★★★  external hard drive
★★★  carbon copy cloner
★★★  clone
★★★  crashplan
★★  backup
★★  migration assistant
★★  raid
★  ccc
★  rsync
★  chronosync
★  wd smartware
★  super duper
★  disk utility
★  airport extreme
★  bootable backup
★  seagate dashboard
★  raid 1
★  file history
★  system restore
  manual backup
  carbonite
  retrospect
  smartware
  wd software
  wd anywhere backup
  carbon copy
  speed concept
  rollback rx
  wd smartware backup
  silverkeeper
  backup mac
  i cloud

Your alternative for time machine is not listed? Suggest!
Speaking about time machine, one probably shouldn't forget about network drive.

Other search terms related to time machine and their ratings are:
★★★★★ network drive
★★★★★ time capsule
★★★★ airport
★★★ airport extreme
★★★ drobo
★★★ mavericks
★★ wd my cloud
★★ exfat
★★ filevault
★★ two drives
★ sparsebundle
★ multiple hard drives
nas drive
iomega
file vault
external drive
You have in mind a companion for time machine and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of time machine in all years. Click on graph for more.
time machine
time capsule
superduper