I saw some time management "expert" on TV a few weeks ago, and while I don't normally care for "expert" advice, she had one particularly good point. Rather than saying, "I don't have time," you should say, "It's not a priority." If it rubs you the wrong way to say it, you should re-prioritize. Her example was a child asking you to read to them. If telling them, "it's not a priority" hurts you, then you need to take the time to read to them and get rid of another obligation.
I have spent a LOT more time reading to Doodlebug since I saw this, but I have also applied it to other areas of my life: primarily money.
Rather than saying, "We can't afford it," I have been trying to say, "It's not a priority." Because the fact is, we COULD afford to eat out, buy more stuff, etc. But it's not important enough to put ourselves in debt or other financial jeopardy. Spending money is just not a priority.
This also justifies some things that I do spend time/money on. I spend a ton of time reading to Doodlebug and playing outside. Others may think this is a waste of time, but to me these are the basis of a happy childhood. We also spend more money on natural/organic foods when we can. These are a priority because I think they are important for the health of our family.
So consider your priorities the next time you think you don't have the time or money for something. Chances are you could make the time or save the money if it is truly important to you.