I want to take pictures at home, but I can't think of things to shoot. Any ideas ?
Follow @dailyshoot on Twitter. I did that for about a month, and having a daily 'assignment' was a great way to get me to take a picture every day (practice makes perfect, after all!) and to learn and try new things (would you believe, that's where I learned about DOF/bokeh?).
When practicing particular techniques, I often take pictures literally of whatever is in front of me at the time. So, for instance, when playing with depth of field, I'll shoot my water bottle on my desk so that I can see the blur in the plants in the background.
Technically, it's a perfect photo. Aesthetically it's boring, so I never show it to anyone. I'll usually delete it and move on.
If you want something to show people, then you start the same place you'd start with any other photograph: what is your intent by making this picture? What story are you trying to tell? What effect on the user are you trying to achieve?
In your house, there's plenty of subject matter for this, just as there is outside of it. Any person can become a portrait; any object can become a still life.
And any pet can get a capshun and posted to the Internet. :-)
My wife likes to do macros and light-paintings of flower bouquets. It's amazing what she can do with an ironing board with a black drop-cloth in a bathroom that has no windows plus a high-grade white LED flashlight and some colored gels or cellophane and a camera on a tripod.
Also look into the Lens Baby lenses. They're a fun, primitive, not-too-expensive tilt-shift lens that gives a different view to anything you shoot with them.