If you are selling online, you need to ensure that the products you are selling are legal. Some types of product - nuclear warheads, etc - are clearly illegal; others are potentially legal, subject to compliance with special regulations. Pharmaceuticals, food and toys fall into this category. Then there's a residual category of products, not given any special treatment, but nonetheless subject to the general law on product safety and quality.
Given the profile of the London 2012 Olympic and Paralympic Games, there will be a real temptation for businesses of all types to attempt to associate themselves with such a huge event. But beware - all that glitters may not be gold for businesses falling foul of any of the myriad of legislation surrounding the Games. One of the conditions attached to London being awarded the right to hold the Games in 2012 was that the organizers had to deliver a “clean games: LOCOG must be able to prevent any unauthorized use of any Olympic-connected branding.