This is one of my favorite devices from Bioware's Neverwinter Nights games. Unfortunately, you can only really get it from the level editor. It works by disintegrating objects that you sacrifice to it, building up a charge based on the value of those objects. It then transfers its charge to another magical object, replenishing its potential number of uses. It's actually a really fun way to relieve yourself of useless junk. So, I designed a Magic: The Gathering card for it. The only difference between the Neverwinter Nights version and the Magic: The Gathering version is that the Magic: The Gathering version accepts power supplied to it from intangible enchantments or from the player him/herself (and that the Magic: The Gathering version's charging is based on mana rather than gold value, as the "price" of all spells is based on mana rather than any sort of economic system).
The credit for this awesome idea goes to the fine folks at Bioware - kudos. (As for Wizards of the Coast, they own both Dungeons and Dragons and Magic: the Gathering, so no special rights-wrangling would have to be involved in such a crossover.) The picture is some random apparatus called the "Faradic Device" I found at Google Pictures. I dunno what it (actually) does, but it looks cool.
Now if you only had an artifact that read any of the following, "-(2):Convert up to 4 charge counter's on a permanent you control, into any counter currently in play." "-(Tap):Move a counter from a target permanent to another target permmanent. Pay 2 life at end of turn per each target permanent you don't control." "-(Pay 2 Life)/(2)/Tap:Sacrifice a Permanent. If It had any counter's on it, you may move each counter to target permanent of your choice. Put/remove from play X counters of your choice. X is CMC of Permanent plus 3, plus number of charge & +1/+1 counters on permanent" "- +1/+1 & -1/-1 counter's don't cancel each other out anymore" -OR- "-When a -1/-1 counter cause's a +1/+1 counter to be exiled as a result of state based effect, put a Negitive charge counter on any permanent you control. -(2)(Sacrifice a charge counter): Change any one counter into a +1/+1 counter. -(3)Exile a Negitive charge counter)Put into play a +1/+1 counter on any legal traget"
"-(2):Convert up to 4 charge counter's on a permanent you control, into any counter currently in play."
"-(Tap):Move a counter from a target permanent to another target permmanent. Pay 2 life at end of turn per each target permanent you don't control."
"-(Pay 2 Life)/(2)/Tap:Sacrifice a Permanent. If It had any counter's on it, you may move each counter to target permanent of your choice. Put/remove from play X counters of your choice. X is CMC of Permanent plus 3, plus number of charge & +1/+1 counters on permanent"
"- +1/+1 & -1/-1 counter's don't cancel each other out anymore" -OR-
"-When a -1/-1 counter cause's a +1/+1 counter to be exiled as a result of state based effect, put a Negitive charge counter on any permanent you control. -(2)(Sacrifice a charge counter): Change any one counter into a +1/+1 counter. -(3)