Re sand/snow: I pack about a gazillion plastic shopping bags. Put a couple inside each other (maybe 3), dig hole, fill bag with snow (pack tightly) or sand, run tent line through all the handles, then bury those bad boys.
Do for every tent line.
Those bag handles are incredible strong if bag/anchor is tripled up (that is, 6 bag loops for tent line to attach to).
This can be used when tenting on rock slab (think moab) with rocks inside bags.
Which i could take credit for idea...read it somewhere.