There are many potions like this scattered throughout the realm that serve no real purpose—they're just rewards, and by "rewards," I mean useless. The only exception I know where these potions have some use is morph liquid.
   
A warm wave of magic flows through your hands as you perceive that.. 
.. this object, a potion of healing, is a potion, 
   and can be referred to as 'potion healing bvumpertan'. 
It is of 5th level, weighs 0 pounds, and is worth 10 gold. 
You can hold it in your hands. 
It glows with a soft light and sheds a magical aura. 
It contains 35th-level spells of 'change sex', 'acid blast' and 'plague'. 
  To make them a bit more useful, how about introducing a "throw potion" skill?  
You'd have to hold the potion in hand before throwing it at the target. 
A precision check is made on the throw to see if you hit the target. 
If the target is hit, the target checks svs.
We could even include it in a book that anyone can read.