Healing Surges as Currency?

So, I've wondered for some time now about the possibility of using Healing Surges strategically as a type of currency. In many sense this would encourage a more tactical and perhaps meta-aspect to 4e, but at the same time it could very well increase the power of PCs at a price, and that's something I like the idea of. 

What I mean by currency is as follows (and keep in mind that this is only me just throwing out un-refined and un-play-tested ideas):

• spend a Healing Surge (without gaining any HP) on your turn as a trigger to having missed with an Encounter or Daily power. 
• 1 HS for an Encounter, 2 for a Daily? I don't like this and I feel like 1 HS for each would be more sufficient. 
• Perhaps have this only usable once per Encounter?
• spend a Healing Surge (without gaining any HP) at the end of your turn on a trigger defined as having failed a Saving Throw and immediately reroll the Saving Throw using the second roll.
• I think that this, too, should only be usable once per Encounter.

Those are just a few ideas I've been tossing around and I like the idea of having to make a rough choice of a short-term gain at the cost of a long-term resource. Now, I do realize there are some issues with this as it favors some classes tremendously over others and could potentially make Durable a very popular feat choice for obvious reasons. 

What do y'all think? Any other potential ideas for the HS currency?