Ask HN: Which crypto would you invest a small amount of money in?

I've pretty much let the cryptocurrency thing pass me by until now, but there's so much hype around it now that I can't help but pay attention!

I have a small amount (£500) which I'm willing to invest in one or more cryptocurrencies, mostly for the fun of it - if I lose the money, so be it.

If you were in this position, which currency/currencies would you invest in, and why? Links to any useful resources (e.g. how to buy them!) would be appreciated!