bash

1. Replace a string without sed
   

   ${VAR/STRING/REPLACEMENT_STRING}

   example:
   

   VAR test ="hallo@sinnlos"
   ${$test/@/#} results in "hallo#sinnlos"
   



2. Indirect assignment of variables

   export "${VAR}"="$VAR2"

   example:
   

   var=sinnlos; bla=tests
   export "${var}"="$bla"
   
   # echo "$sinnlos"
   # test