There are third party memory card solutions out there... essentially they hijack the cart slot and allow you to stick in a standard micro SD card to use as storage.
I have two of the standard PSV memory cards (I think a 4gb one that came with my Assassin's Creed bundle, and another 32gb one that I spent like $100 on when the finally dropped the prices into a realm that was at least within viewing distance of sanity), but being able to stick in a cheap-o micro SD card and have ALL the games I purchased (and some extras...) is pretty great.
And because I feel like I'm legally obligated to say this as a Vita owner, hacking the thing was the best decision I made outside of buying the handheld in the first place, when it comes to the PSV. It's way easier now than when I initially wanted to try (and was too scared to do so when the handheld was still being supported), and as long as you follow up-to-date instructions you should be golden.