The Builder buys 90 gp of bricks (900 bricks), and Builds a handheld item that grants Scribe Scroll and Brew Potion, which he then gives to the Cleric. He buys another 90 gp worth of bricks, and Builds a handheld item that grants Craft Wondrous Item and Craft Magic Arms & Armor. He then buys another 90 gp worth of bricks, and Builds a handheld item that grants Forge Ring and Craft Staff. He then buys another 60 gp worth of bricks, and Builds an item that grants Craft Wand.
For 330 gp, he's now handed the Cleric almost the entire item crafting line (Craft Construct requires both Craft Magic Arms & Armor and Craft Wondrous Item, so can't be done via Lego with handheld items). The Cleric need only use one at a time.
He could do the same with metamagic feats. Or Sudden Metamagic Feats (some of them, anyway). Or Martial Study / Martial Stance (Tome of Battle: Book of Nine Swords) feats. You can get some serious crazyness going on here at fairly low levels.
Perhaps if the feat components had to be made almost entirely out of Soul Bricks? Hmm...