I've been kicking this basic mechanic around for a while, and I need some more input before I can go any further. For lack of better terms, I'm going to be calling the system "Flux", and users "Originators". The idea behind it is to have a character who can adjust between being more warlock/binder-like and more Vancian-like, depending upon how you prepare at the beginning of the day.
The basic mechanic is that each character has two statistics, Refresh and Capacity, which combined determine your Flux Points (FP).
Each round, you regain a number of FP equal to your refresh, up to the total of your capacity.
At this point, this sounds a bit like a faster-recharging version of psionics. However, powers work in a slightly different, incarnum-like, manner.
At the beginning of each day, you can "slot-in" different powers. Each power has an Upkeep and a Reserve; Upkeep reduces your Refresh for the day, and Reserve reduces your capacity for the day. Costs and benefits can be scaled upwards based upon your Originator Level.
For example, pulling numbers out of nowhere, a second level originator has a refresh of 3 and a Capacity of 10. He can slot-in "Vestments of Acid", which has an Upkeep of 2 and a Reserve of 5.
This gives him acid resistance 5, acid splash at-will for free, and the ability to spend two FP to add d6 acid damage to his next attack (which could be his acid splash).
A power that you've slotted-in can also be "burned", which gives a one-time effect, but then prevents you from using any of its benefits for the rest of the day. So you could burn Vestments of Acid to deal 2d6 acid damage in a 10' spread, for example.
So here's a few examples of different powers using this mechanic. Just playing around at the moment, trying to feel out the concept; balance isn't exactly expected.
Vestments of Acid (first level)
Upkeep 2, Reserve 5
Scaling: X starts at zero, add one to X for each additional 3 points of reserve invested (to a maximum of X=5)
Continuous: All attacks that require an attack roll add X acid damage.
Continuous: Gain acid resistance 5+X
At will: Acid splash, as the spell, with your originator level as the caster level.
Investment: Spend 2FP to add d6 acid damage to an attack, up to a maximum number of FP equal to your Originator Level.
Burn ability: Deal (1+X)d6 as a 10+5X' burst, at a range of 30+10x feet.
Telespam McMuppet(Fifth Level)
Upkeep 6, Reserve 0
Scaling: X starts at zero, add one to X for each additional 5 points of reserve invested (to a maximum of X=5)
Continuous: Anyone teleporting into a square within your reach provoke an AoO.
Investment: You may teleport up to 5X feet as a standard action. This distance increases by 5' for every Two FP you spend.
Burn ability: Teleport (as the spell) with Originator level as caster level. Subtract X from your familiarity roll.
Mutability of Flesh(Third level)
Upkeep 0, Reserve 20
Scaling: X starts at zero, add 1 to x for each point of upkeep you add (to a maximum of X=5)
Continuous: Gain DR 1+X/--
Activated: Gain Fast Healing X for a number of rounds equal to your OL.
Investment: Move action: spend 1 FP to add 1 damage to all your melee attacks for X rounds, up to a maximum of half your OL(doesn't stack with itself, duh)
Investment: Swift action, spend 1 FP to increase your land speed by 5' for this round, up to a maximum FP of half your OL.
*If X is 1-2, gain a climb or swim speed at your base land speed.
*If X is 3-4, gain a fly(average) or burrow speed at your base land speed, and your speed increases apply to climb and swim.
*If X is 5, your fly speed is perfect, and your speed increases apply to fly and burrow.
Burn Ability: Gain X temporary HP per OL, DR 2X/--, fast healing 2X and you can move double your speed for OL rounds with any movement modes you could access with the investment.
So, yeah. It definitely seems like it could be cool (I suppose I could start off by making a slightly-inferior set of powers that mimic the warlock, then shifting around options), but coming up with a whole list of abilities is going to take a while, and I'd prefer to get some feedback before I did anything else.