Which is better to use as sand?

graham cracker crumbs... I have even added one oreo or vanilla oreos - nilla waffers (just the cookie not the cream), a few poppy seeds to add some other demension of color. Never sanding sugar - who wants a mouth full of grainy sugar. I don't think i would do brown sugar either. (just my opinion)

I think it's ok to use brown sugar (I have) if you're just doing it in a small area. If you're covering a large area, I would definitiely do crushed graham crackers or vanilla wafers!

Graham cracker crumbs with a little yellow or gold sanding sugar added for sparkle.

I use a mixture of graham cracker crumbs, vanilla wafer crumbs, brown sugar and white sugar from an article in ACD.

for the beach cake I just did I used crushed graham crackers mixed with brown sugar...

I grind up vanilla wafer cookies...they wrk great and taste great...I have a couple beach cakes with sand, here is one
http://cakecentral.com/modules.php?name=gallery&file=displayimage&pid=1152388

thanks everybody!

I prefer the vanilla wafers too. I have a beach pic posted you can look at to see if it's the look you are going for.