Some of the Combos

Caltrops + Sydri, Galvanic Genius = Any attackers without indestructible immediately die. Sydri turns Caltrops into a 3/3 with lifelink and deathtouch. Both keywords trigger when damage is dealt and you know the rest.

Sydri, Galvanic Genius + Voltaic Construct + Thran Dynamo = Infinite colorless mana. Animate Dynamo, tap it for 3 colorless, use 2 of it to untap with Construct's ability, wash rinse repeat for infinite colorless. Replace Dynamo with Gilded Lotus to produce infinite colored mana.

Sydri, Galvanic Genius + Mycosynth Lattice + Dross Scorpion = Infinite Land Destruction. While Dross Scorpion and Mycosynth Lattice are out, tap a land that produces blue, animate an opponent's land into a 0/0 that immediately dies, Dross Scorpion will see an artifact go to the graveyard, therefore untapping the blue land you spent to animate the land. Wash, rinse, and repeat until all lands aside from yours are destroyed.

Thopter Foundry + Sword of the Meek + Krark-Clan Ironworks = Infinite Life and Colorless Mana. Step 1) Sac Sword to the Foundry, producing 1 life and a thopter token. Step 2) Sword comes back equipped to the thopter. Step 3) Feed the thopter to ironworks producing 2 mana. Step 4) Use one of the colorless to feed the sword to the foundry, repeating the cycle.

Sharuum the Hegemon + Phyrexian Metamorph/Sculpting Steel + Disciple of the Vault = Infinite Life loss. Start by having Sharuum and Disciple on the field, then play Sculpting Steel or Phyrexian Metamorph copying Sharuum, put the legend rule on the stack, sacrifice original Sharuum, use the copy's ability to recur the original, sacrifice the copy, repeat till you win.

Rings of Brighthearth + Basalt Monolith = Infinite colorless mana. Tap Monolith for 3 colorless, use 2 of it with Rings' ability to copy the tap trigger netting you 3 more colorless that you use to untap Monolith. Each time this cycle is performed, you will produce 1 "free" colorless mana.

Pili-Pala + Grand Architect = Infinite Coloured Mana. Use Architect's ability to turn Pili-Pala blue, tap it for two colorless, untap it with its own ability producing whatever color is needed.

Infinite Colored Mana combo + Memnarch = All Your Base Belongs to Me. Feed infinite amounts of blue mana to Memnarch to take control of everything.

Walking Ballista + Infinite Mana Combo = Infinite Damage. Use an infinite mana combo to cast Walking Ballista for 1000 (just an example), then unload until all opponents or creatures are dead. Add Sydri, Galvanic Genius for some extra kick.

Darksteel Forge + Mycosynth Lattice + Nevinyrral's Disk = Blow Up Everything But Your Stuff. You have indestructible artifacts, they don't. Nuff said.