Planeswalkers have been animating enormous artifacts since the time of the Limited Edition Alpha set, and the current Mirrodin block hasn't slowed them down any. Want an old-school combo? Enchant Aladdin's Lamp with Animate Artifact and swing for 10. Want some more animated-artifact goodness? Check out these tricky transmogrifying spells, old and new:
Titania's Song - Antiquities introduced this green enchantment to do a mass animation all at once. Note that the artifacts lose their normal abilities under the Song, in exchange for getting a power and toughness.
Xenic Poltergeist - Antiquities also brought a 1/1 creature that could awaken a single artifact for the cost of a tap.
Karn, Silver Golem - Fast forward to Urza's block. This Golem Legend brings with it the power to awaken massive armies of artifacts for temporary but powerful swings into combat. From this point on, artifact-animating spells in Magic all allow the artifact to keep its prior abilities.
Karn's Touch - The appropriately-named instant from Mercadian Masques is a one-off effect of the pacifistic golem.
Toymaker - Toymaker also replicates Karn's ability, this time as a Spellshaper, turning one card each turn into Karn's Touch. But surely you wouldn't use it to make a tiny automaton out of a Chromatic Sphere -- use it on Summoning Station and it's a Enormous Stomper Maker!
March of the Machines - Possibly the granddaddy of all the animating spells. Mirrodin introduced this enchantment with sweeping powers similar to Titania's Song, but in blue, and with the added benefit that the artifacts keep their abilities. So now your Darksteel Ingot stays indestructible and can still tap for mana -- and your opponent's artifact lands just became 0/0 and headed for the graveyard.