Mana Manipulator
Below is a copy/paste of a post I made in the Strategy Forum a month and a half ago. I'm posting it here because I'm getting tired of my team raging when I pick Mana Manipulator.
tl;dr: Mana Manipulator can be an incredibly cost efficient item. It deserves a better public opinion than what it presently has.
Higher level players have reached a consensus that a Philosopher's Stone on supports takes far too long to pay itself off to justify delaying the Sightstone for so long. Further, the opportunity cost of spending 700g on regeneration means substantially fewer wards in the early game as the gold generator and its components are purchased. Instead, supports have been spending tons of gold on potions, letting their regeneration needs burn a hole in their pockets in the short term in order to get the immensely powerful sightstone operational as soon as possible.
But here's some math it seems like nobody's noticed:
Assuming a laning partner that can use the mana (not always true, but frequent enough), Mana Manipulator generates a mana potion's worth of mana every 50 seconds. At a price tag of 300g, it takes 300 / (35 / 50) / 60 = 7.14 minutes of laning for the mana manipulator to pay itself off compared to buying potions. That's about as long as it takes for the turrets' newfangled armor bonus to wear off - and assuming no crazy action, probably about as long as you'll spend away from home before your first recall.
300g isn't trivial to fit onto a starting build. To keep up with the Joneses, you'll probably want to get the initial gold mastery and either take 3 wards or 2 wards and 2 health potions (or other permutations if pink wards are needed). It's workable, particularly on champions on whom the mana generation equates to health regeneration. 300g is, for a point of reference, the same price tag as cloth armor and machete.
The item also scales quite nicely into the late game for its cost - assuming, of course, that mana regeneration is something your allies care about. It is true that Shard of True Ice is weak, but at its miniscule price tag, Mana Manipulator doesn't obligate you to combine it into another item. It can be sold back for only 90 gold lost total, in case the game goes late enough that you need the item slot again.
It's not something that belongs on every support or every team composition or every matchup, but I've been having a lot of success with the item and I think it deserves more attention.