Despite what some folks believe, you really don't need to plan months in advance to have a fun trip to Walt Disney World. There are lots of Florida Annual Passholders who make impromptu trips throughout the year. Outside of holidays, it's really not difficult to find a decent place to stay.
Certainly, you're not going to get the most sought after FastPasses and you might have to eat at slightly off hours. But, if your group/family is small (4 people or less), it's not as impossible as people believe.