My friend is exploring this card. There are a lot of interesting combos you can run. Nothing that's quite tourney viable, but who cares! It's a casual player's dream card.
Here are some things that I find intersting:
You can use it to break symmetry with Quicksilver Fountain. Use the conduit to keep removing the flood counters from your land. If you don't have a good home for the counter, there's nothing illegal about putting a charge counter on the conduit or the fountain - they just don't do anything. Great way to color-hose the board.
You can create a lock on spells with Decree of Silence. The conduit can keep removing depletion counters, so it never runs out. Of course this is super cheesy, way too expensive, and only helps you if you've already got control of the board.
My friend *almost* locked me out by comboing this with Wall of Roots and Spike Weaver. You put a -0/-1 counter on the wall to adda green. You use the green to remove a counter from the weaver and fog. You then use the conduit to remove the -0/-1 counter from the wall and put a +1/+1 counter back on the weaver.
Anything that puts counters on things as a form of payment is good with this card - Serrated Biskelion, Cumulative Upkeep, etc.
Also, the ability to add charge counters to things adds more utility. +1/+1 counters are nice, but aggro-combo doesn't often work too well, so artifact manipulation is better.
Things that use charge counters that you might want to look at:
Riptide Replicator: Why pay a bunch of mana for it now when you could just pay 4 and let it build?
Lightning Coils: Why kill your stuff just to get 3/1 hasters? Do if for free, do it organically!
Chalice of the Void: HELLO! Adjustable Chalice, ho boy!
Magistrate's Scepter: Infinite turns? Not likely, but lots of extra turns? Easy.
Just some brain food.