Tie-Out Stake - I think, that's how it's called. I was thinking, does it work in sand? you know, on beach. I know it's too hot to be in the sand, but you can't always hold it in your arms, can you?
For those who don't know what are Stakes, are the ones which stucks into the ground, and you can hook your dog into it.

http://www.blackicedogsledding.com/page19.html

i don't think that works in sand, couse in arctic, snow is hard

I would think it would work in sand. It's the same principal as porting a ship. You dig a pit in the sand down to wet sand where it can get some bite to anchor. For extra hold bury it and pack wet sand around it.

Oregon Dune Mushers might be able to help you.
http://www.oregoncoastmagazine.com/oregon_coast_dune_mushers_mail_run.php

Are you wanting to tie out your dog or are you hooking up to a cart/scooter? That kind of makes a difference in what you are looking for.

You have to try a little harder to get the stake to actually stay in the ground in sand. This is coming from personal experience. You generally have to dig to find the wetter/harder part of the sand to then stick the stake in the ground and you want to make sure you have to beat it with a mallet or hammer to get it in the ground well enough to hold a dog.

Yeah getting anything to stay in sand is hard. We once took Kato and Karma to the beach in Tahoe...thinking that they would be nice well behaved dogs, we stuck a couple of stakes in the sand..two minutes later they were both running up and down the beach with their tie-outs still attached to the stakes. Yeah, bad idea. Luckily, we were able to grab them, and no one got hurt!   

Ehh, no problem, i can just hold my dog allways There is more fun, when you're not alone But This is what people say in our country: Animal rescues and federations are really trying to get a dog beach, but health federations and stuff: Dog poop and urine is really dangereos to people and especially kids, when play in the sand. Not talking about water. But then commenters (and i): That is so not true. Don't people poo and pee in the water? and nobody tells them anything, and doesn't even care. AND what about old dirty homeless and spending money on beer people? They come and get's all the bacterias in the water and sand.And btw, dogs don't really poo an pee in water. I HATE MY COUNTRY, they are so stupid... like look at other countries, they are always DOG FRIENDLY. uhh, just, people are so freakin stupid.