Here is how I repaired my vacuum cleaner. The hose was broken. I used Blender to model these two parts and printed them with my Ultimaker. I screwed the big one into the hose and inserted it into the original vacuum cleaner part and finally stuck the small part to fix the whole.
Like the idea of being able to fix the vacuum cleaner, but would really like to see the tutorial in blender on how to make the part! Already got the printer, now need to learn blender. 
THIS is where I see 3D Printing being useful. The I need it now fix.
Chet Wyatt imagine all the people who needed this part and what they would have to do to get it shipped, not to mention the waiting time. I agree with you, what a great way to instantly get the part you need. Thanks for sharing!
Oooh, cool. I need to make an adapter almost like this for my shop vacuum instead of using duct tape. Do I find this object somewhere, like on http://www.thingiverse.com ?