I trade, so I basically buy and look to sell for a profit within a day or so. Made about £1000 in the last 5 days but the markets seized up so will have to leave it for a week.
I've sold all of mine now, but there's an escow option on there so it's nearly impossible to get scammed. You can also buy for cash which will usually get you a better rate than buying using online banking.
Got some sleeves of these http://www.google.co.uk/imgres?imgurl=http://www.ciggiesworld.com/product_images/u/131/MarlboroLights__94748_zoom.jpg&imgrefurl=http://www.ciggiesworld.com/marlboro-lights/&h=520&w=327&sz=33&tbnid=Lv6ouCBI_FxbUM:&tbnh=90&tbnw=57&prev=/search%3Fq%3Dmarlboro%2Blights%26tbm%3Disch%26tbo%3Du&zoom=1&q=marlboro+lights&docid=blmDE0R48F1YbM&hl=en&sa=X&ei=Wb0FT4_JBYGcOs273bEP&sqi=2&ved=0CDsQ9QEwAg&dur=427
£40 each retail £75