Plywood boards do not usually bring about a picture of a cool furniture, more likely a structural part of any project, but if you look a bit closer to some ideas that use this material, you might be pleasantly surprised. Plywood comes in many kinds-wood wise and variety of thickness which makes it a nice and easy material to build with. One thing is to be careful about is the quality and flatness of a board. You do not have much room for error in this department, heavy belt sanding or planning a plywood is out of the picture really-if you do not want to destroy the board, so choose wisely, look closely and pick the most perfect piece.
OSB boards are totally different texture, but also make an unique building material, rough look combined with modern design and other materials like metal or concrete make a super cool combination, definitely not something you can buy at IKEA.
Look up some vids on Youtube, you can literally find tons of tutorials on the subject, most of the wood working guys keep it real simple as well, I also learn from them a lot on regular basis.