I was posting on the forum and got one through a random event.

what does it do aside from giving you an achievement?

It gives you a random 50CSC item from the CS like a Yellow Cheek star sticker or some sort of hat or a ribbon choker

oh so just a 50CSC item at random, I think I'll sell it then. a friend told me 6 credit points and it surprised me that 6 points would sell for 1.2M O_o

you can also get a random small amount of CSC. You can see people's results in a thread in Games subforum, and there might also be a thread in General.

how can I get this ticket?

it's random when posting on the board. or you can buy it from the shops.