Donna Goldsmith of the Association For Computing Machinery stresses that this is as true for trade and consumer shows as it is for other marketing media. It's important to have continuity among the materials you provide prior to a show, during the show, and even afterwards. The firm develops the logo and theme, and designs all publications, signage and merchandise. The same design and color scheme was also used throughout the show site. Even printed materials distributed after the event carried the show design.
Items vary from year to year.
T-shirts and coffee mugs are always available, and travel totes, playing cards, calendars, shot glasses, Polo shirts and key chains have been sold in recent years. At this year's conference I saw people wearing T-shirts from five and seven years ago. Historically, ACM hasn't amortized design costs against these items. Otherwise, we wouldn't bother. We also view this as a form of promotion.