Not talking about display, but experience and giveaways. How do you be the coolest booth in the building?
Look into pitchmen. Joel Bauer started as a pitchman, in which he used his magic act to get attention for his client's booth. He understands that the unexpected and entertainment are big factors of attention.
Giveaways...hey, it's possible to give away a lot of things and not get anything in return. Build a feedback loop into whatever you give away: if it's a contest, make sure they have to log into your site to see if they won, for instance. Or call you. Then you get another chance to communicate with them. Match the giveaway to the theme and audience. Giving an iphone 7 away to a crowd at a power generation show isn't a great fit and isn't memorable.
I've heard an example of co-opting other people's booths. This is interesting because you expand your distribution channel at little cost. The idea is you ask if you can put your brochure on their countertop, and in exchange you'll by their crew lunch. Of course this works best when your products are complimentary and not in competition. Imagine if you got 4 or 5 of these to work with you. "Everywhere" the attendees go, there's your brochure. You must be legit.
But the key thing is: make sure you get the conversation AFTER the show is over. Collect business cards; screen a little for fit; book the next conversation. Don't try to do everything at the show. Yes, it's possible to set up big deals right there; however, you probably won't and your objective should be to get awareness of you and your brand into your target market's (distributor's) head.