My first idea was to make an enchantment that removed all land types, and replaced all text with ", Pay 1 life: Add one mana of any color to your mana pool". I realized it would probably go over better if I made them triggers. In an attempt to increase the casting cost, I started playing with ideas... Manabarbs and Mana Flare sounded good. But I had a really hard time accepting that no one else hadn't done this before. (they had. It's called Overabundance). Besides, I needed to get to 5cc to get a casting cost and had a touch of hybrid, had some colorless, so that this could end up in a multi-color deck. So, here's a bit of extra boom.

Yow. Overabundance plus another copy of Heartbeat of Spring. Wow.

(I had a silly Overabundance / Storm Cauldron deck, back in Invasion time. It aimed to make casting spells hard for people, and certainly accomplished that, but it didn't really accomplish anything else.)

I remember when Storm Cauldron came out. My friend had a very good U/W 'The Deck' style deck, and insisted that the Cauldron was awesome, because it made people wait to cast their spells, while he eventually drew into a counter. His Jayemdae Tomes looked very silly.