"Instantaneous" use of continuous advantages?

[Venatius]

In efforts to patch together a system somewhat emulating the "Charms" system used in White Wolf's RPG "Exalted", I've found myself looking at a number of normally always-on GURPS advantages and wondering how to set up having them applied, with an FP expenditure and/or activation roll, only for an instant. An example might be Striking ST for a single attack, Lifting ST for one second, Super Jump for a single leap, Enhanced Dodge against a single attack, etc. I have not yet found an existing way to do this in the rules though. The "Maximum Duration" limitation in Powers comes closest, but it requires an ability normally be "always on", the smallest span of time it gives is thirty seconds, and it gives a five-minute shutdown afterward. The "Active Defense" version of the "Requires (x) Roll" limitation is nearly perfect, but only applicable to defensive abilities.
I can understand something like what I'm looking for not existing, because unless you were to combine it with other limitations, it wouldn't really present much of a limitation! It looks more and more like I'll have to fabricate something for this, but I despise redundancy, so if an appropriate modifier or optional rule exists to accomplish this, I'd rather use (or at least look at) it. Again, the aim is to have abilities that, once triggered, persist for a single turn, a single action, or for only one second, but can be reused freely - as long as you make your activation roll, pay the cost, or whatever else. IDEALLY I'd like something that would work just by paying FP cost.
Does such a thing exist anywhere in the vast landscapes of material out there?

UPDATE: Well I'll be. I just stumbled across "Reduced Duration" on page 21 of the delightfully illustrative Psionic Powers. I suppose you could apply that to the default one-minute duration granted by a continuous ability with Costs FP, couldn't you? Feel free to correct me if I'm wrong, or if I'm correct, to chastise me for my tardy realization while I hunt for some sort of thread deletion function.

[ericbsmith]

p. B111 Costs Fatigue, at -10% for 1FP/sec.

[Venatius]

How... how did I miss that? It was... right there in the text for the very limitation I was initially looking at.... I'm going to go crawl into a hole, if you will kindly excuse me.

[Joel]

Originally Posted by ericbsmith

p. B111 Costs Fatigue, at -10% for 1FP/sec.

Problem with this would be that you'd technically have to ad Reflexive +40% to be able to activate your ability in response to an attack (which you'd want if you want to emulate how charms work).

[Venatius]

Originally Posted by Joel

Problem with this would be that you'd technically have to ad Reflexive +40% to be able to activate your ability in response to an attack (which you'd want if you want to emulate how charms work).

For the abilities that do 'activate themselves' at the player's option after the fact, yeah, that's actually quite true. Seems odd. If it cost a single FP, it looks like you'd end up paying MORE just to have the advantage as one you have to toggle on and off! Though, does it actually specify turning on a Costs FP ability requires an action? Because Reflexive specifically removes the need to use Ready or Concentrate to activate.

[Joel]

Oops, now that I read it I guess it actually doesn't say it needs any kind of action. I only kind of assumed it did because the Switchable modifier requires you to take a Ready.

[ericbsmith]

See Powers p. 153-154+. Basically, Costs Fatigue turns an always on ability into a switchable one. In order to make a switchable ability turn on instantly requires Reduced Time (in this case, one level will do), or Reflexive. And, yeah, this is one of those bogus areas where limiting an ability to get the effect you desire can wind up costing more points than the vanilla always-on ability.

[Bruno]

Originally Posted by Venatius

UPDATE: Well I'll be. I just stumbled across "Reduced Duration" on page 21 of the delightfully illustrative Psionic Powers. I suppose you could apply that to the default one-minute duration granted by a continuous ability with Costs FP, couldn't you? Feel free to correct me if I'm wrong, or if I'm correct, to chastise me for my tardy realization while I hunt for some sort of thread deletion function.

Yep, that would totally work with Costs FP, and it certainly helps make up for the slightly degenerate condition where your "Instant on, use for one minute, loose an FP" power costs more than the "Always on no cost" baseline.

[Pomphis]

Why degenerate ? You will only buy it if you believe that it will sometimes be useful if it is off.

[LemmingLord]

You could just purchase the advantage with nuissance effect and wing it. Sounds like a 15% nuissance effect to me (instantaneous but costs fatigue per second?).