I'm tired of NO

I just finished reading an article about how it's so important for kids to have unstructured play. I find that tricky to accomplish unless we get together with somebody else. I know why parents schedule so much of their kids time. Because if you don't your kids drive you crazy. If we stay home all day, Ben drives me crazy. I don't really want to go anywhere today because we are all sick with colds, so Ben is driving me a little crazy.
I get so tired of saying no, even though right now I only have one kid I really have to say it to.
So far today here are a few of the things I've said "no" to.

• Can I have candy? (Ben asks this every single morning within minutes of waking up and at least a dozen times during the day. I love candy, but sometimes I get close to throwing it all away so Ben will quit asking me for it.)
• Can I watch tv?
• Can I have a snow cone?
• Can we play Lego Star Wars? (No, that is something he plays with Chad. I don't really like playing video games, but if I ever do I won't let Ben see me otherwise he would be asking even more during the day to let him play.)
• Can we go to Grandma's? (No because my dad had surgery yesterday, and we don't want to get anybody at my parent's house sick.)
• Can we go to Lagoon?
• Can I play a computer game?
• Can I play with the kids? (We can't play with them every single day.)
• Can we go to the park? (It's raining, but we might go anyway.)
• Can I play the caterpillar game? (No because we can't play it when Jack's awake because it has small pieces.)

A couple of weekends ago we were at my Grandpa's cabin. When we woke up the first morning, Ben asked if there was a computer at the cabin. When I told him no he said he wanted to go home. He's three years old! You'd think we let him play computer games all the time. In reality it's only once or twice a week.

I'm wondering how to get Ben to have more unstructured play time when he's constantly asking me to entertain him.