What's inside your expensive ink cartridge? Well, dye. But that's just a teeny, tiny fraction of what's inside those cartridges.
Besides dye, the rest of your "ink" is a complicated cocktail of chemicals designed to orchestrate inkjet magic. There's solvents inside that control the viscosity of the ink, keep the solution from evaporating and try to prevent your printed paper from doing that curl-up thing.
But mostly? It's just water:
The ink in inkjet cartridges can be as much as 95 percent superpure deionized water. Yet at more than $3 per milliliter, it would be cheaper to print your vacation pics with Dom Perignon.
Consider that next time you're handing over two $20 bills to the cashier at Office Max.
Oh, and remember: Your printer throws away 40 percent of the ink in each cartridge anyway. Happy printing!