Boon PULP Silicone Teething Feeder: $5.99
Munchkin Miracle 360 7oz Trainer Cup: $12.64 for 2
A friend recommended this cup after she had success with her son. There is a version for big kids that does not have handles and can hold more volume, but this size is perfect for our 18 month old. It is relatively spill proof and easy to clean. It is also recommended by dentists. The way it works is fluid fills up the white part, and a small amount of suction around the edge allows it to flow slowly.
This was a recommendation from the speech therapist who did our little one's swallow study. You can squeeze the belly and a little bit of fluid comes up through the straw, allowing your child to get a little bit of at a time. Eventually, it helps them with their suck and for us, helped out daughter learn to drink from a straw.
This was a random stroke of genius walking through Ikea. Our daughter doesn't particularly care for the baby/kid flatware we had, but liked ours, so we got this safer option for her. I eat with it also, encouraging her to use hers.