The title was originally going to be "5 Ways." Then I couldn't find a 5th way…so here we are.
The black slice of the color pie is normally filthy with recursion. Unfortunately this is limited mostly to creatures and not permanents of other varieties.
Limited does not, however, mean zero. There are 4 spells I have found that help get you more bang out of your trinkets and gew-gaws.
I shall order them last to first, in order of usefulness to me alone.
4)Least useful! Moriok Scavenger. The Sanctum Gargoyle of black. Only it doesn't fly or recur itself for crazy Sharuum interaction. Oh WAIT…and its only an artifact CREATURE. So this is actually strictly worse than Gravedigger unless you are building some kind of rogue tribal deck.
Note: Remember kids, he's a Gravedigger, not a Grave Robber. Gravedigger is gainfully employed by The Cabal in their corpse/undead relocation division. He has insurance, vacation time and a generous retirement package. He worked hard with a shovel to get to where he is today, and by no means could be considered some type of thief.
3) Scrounge. Scrounge is a Bribery-type spell that grabs a valuable artifact out of your opponent's graveyard and puts it into play under your control. A good spell to use if your play group plays a lot of big, powerful artifacts. Usually they have to be blown up first, but black is also pretty good at milling so you might be able to catch a lucky break. I would much rather depend on my own artifacts however, since they tend to mesh better with the rest of the cards in my deck.
2) Geth, Lord of the Vault. Geth is pretty awesome in most ways. In fact, if this were a list of overall usefulness, Geth would definitely be near the top. He only grabs stuff out of opponent's graveyards again, but he can do it over and over again. And the ability is glued to a big stocky body you can swing in and attack people with. I am currently on the look-out for a copy of him.
1) Beacon of Unrest. Woo Woo! Works on both creatures and artifacts! Grabs 'em out of any graveyard! Puts 'em directly into play. Shuffles back into your library to use again and again! After a quick look around the Internet, it appears Beacon of Unrest is used in just about every black EDH deck every created. And its easy to see why. So the Beacon gets slapped into my search list as well. And with printings in Planechase, Archenemy, Tenth Edition and Fifth Dawn, there has to be a copy laying around somewhere.
Edit: And I see now that fully half of my card selections don't actually recur anything from YOUR graveyard, just opponents. And then Moriok Scavenger doesn't really count either, because he sucks.
So really, the title of the post probably should have been "Beacon of Unrest has a unique, powerful artifact returning ability in mono-black." There is no other solution!