The most important aspect of a trade show is to get the message out to potential customers that you exist, what services and/or products you can offer, and how to get in touch with you. Giveaways play a role in reminding customers that your business is an option they should consider. The most important thing to give away is contact information and a good-quality brochure describing your company, its products, and its services. Videos that can be played back on a computer are handy, but I suspect many end up tossed in a drawer or used as coasters. It is also very costly to produce a professional presentation of this type. A small giveaway can be very effective, but only if it works as expected and is useful. You don't want ot be the company remembered for handing out "those crappy pens", as I recall one business so labelled. A giveaway that someone can pass along to others in their workplace is also quite useful. The more people who pick up and use the item, the more who are exposed to your company name. I feel that large prizes have a more limited appeal and don't reach customers as well. The first thing to consider is whether the prize will be used by the customer's company or by the winner personally. A prize given to an individual reaches only one person. They may appreciate it and your company, but if they change jobs next week, no one benefits. A prize to a company reaches more, but only if your business is identified with the item. Some companies do not permit employees to enter such contests or to keep prizes they win. Problems can arise if a prize intended for an individual is won by a government employee, since the government sector has strict regulations concerning conflict of interest. (That these regulations can be broken makes no difference, because they can and are strictly enforced by most managers.)

Smaller gifts. I think everyone likes to get a "gift".