The best replacement for asf is wmv.

The best alternatives to asf are rated as following:
★★★★★  wmv
★★★★  avi
★★★  gsf
★★  sfig
★  asf warhammer
★  ngt
★  dav
  asx
  intel amt

Your alternative for asf is not listed? Suggest!
Speaking about asf, one probably shouldn't forget about virtualdub.

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



Google Trends

Scale is based on the average worldwide traffic of asf in all years. Click on graph for more.
asf
wmv
avi