M.C.
I am also Melissa C. and I feel your pain. My son will be 4 in Sept. and we've had the same experiences you have. He is very content in his diapers, no matter what incentives we offer. His preschool won't let him come back next year unless he's completely potty-trained, no assistance needed. I'm very worried.
He is interested in the "sinking the cheerios game" but doesn't have the patience to wait there until the tee-tee comes. I'm going to try the "no pants outside" trick next. Hoping the neighbors won't mind since we don't have a privacy fence! I'll be anxious to read what advice others give you.
A mom in our preschool class said she started putting cloth diapers on her son. He didn't like that wet feeling, so that prompted him to start using the potty. I haven't had the energy to go that route (who wants to wash out dirty diapers?!) but the suggestion of a pull-up over underwear sounds interesting. Good luck to both of us!