While Doctor Strange, Surgeon, The Wind Crystal, Boon Reflection, and Alhammarret's Archive multiply your life gain
It can hit almost any permanent, and depending on what colors your opponent is playing, it can be very difficult for them to remove the Ring
The most notable money cards would be Boros Charm and Swords to Plowshares
Bringing back the foil loophole and increasing the supply of Reserved List cards through Masters sets, Secret Lairs , and other "premium" supplemental products would be a win for both Wizards and players and likely not as bad for collectors as some would like you to believe
Be it as a Commander or in the 99, these cards are useful for any Commander deck that utilizes Lifegain as its main win condition