you can randomly give stuff out but basically any form of gambling is not allowed. If you do choose to do something just be careful that there is no gambling element involved.
well i think you already do good if you buy up stock on the market where only 1 or 2 items for a certen price are on , that are players trying to sell items for a decent price , and not to a way to low buy order price
I do it also , taking a hand full of isks and go on a shopping spree , buying mostly low priced items , (under a mil) so that alot of ppl have a blinking wallet and can respend it , items will never see the market again i drop them in a container to gather dust