Stupid proprietary memory cards...

Sony needs to use normal SD/micro-SD cards in their handhelds, like the 3DS and every other mobile device out there. Those expensive proprietary cards are holding the Vita back.

Are there any cheaper 3rd-party cards for the Vita like there were for the PSP?

The reason they're proprietary is two-fold:

1. They're out to control the profit on most accessories

2. The PSP was pirated so much that they decided to control it by making the memory cards tough to crack, but in doing so, it made them more expensive. However, this extra cost isn't what makes the cards so expensive. That is just Sony being greedy.

In answer to the 3rd party solution, there is none :(

Yes, that would be great.

Nope. Bend over and pay $50-$100 on a decent sized memory card.