I have been using a ceramic tower heater, very small and compact for over a year now (when it's cold). Most (maybe all?) of them come with a spring loaded button on the bottom, so that if it is knocked over, the spring pushes the button out and that make it shut off immediately.
Here is a picture of the one I own, I liked the compact styling. (7.5 inches diameter by 14.5 inches tall)http://www.amazon.com/gp/product/B002Q8HDJA/ref=as_li_ss_tl?ie=UTF8&tag=lefty-20&linkCode=as2&camp=217145&creative=399369&creativeASIN=B002Q8HDJA
They do not glow red like the old heaters, so you can't see them in the dark, but you can surely feel their warmth in plenty of time not to trip over it. Mine is cool to the touch on the bottom and sides, except right where the metal screen in front is located, can get pretty warm.
I have set mine on the vinyl floor, the carpet, the table and the counter top, at various times. Mine has two settings, 1500 watt and 800 watt. I tend to set mine on a table or counter if I am using it at night, so neither the dog nor I can trip over it. By day, I put it where ever it suits me best.
If I leave the motorhome with the heat running, I make sure it is in a safe place before I do so. Most often I just turn it off completely, because it heats up the place so quickly anyhow.
Recently I mail-ordered a tiny 200 watt ceramic heater, will let you know what I think of it, once it arrives and I get to use it. I was thinking it would be a good bathroom heater when needed, or that it might take the chill off cold feet. Someone said you could own multiple 200 watt heaters rather than one big heater, but I don't want multiple heaters everywhere, but I could see where for me, the 200 watt heater could come in real handy at times. It is only 4x4x6 inches, perfect for what I intend to use it for (I hope!)
Here is a picture of that little gem:http://www.amazon.com/gp/product/B003XDTWN2/ref=as_li_ss_tl?ie=UTF8&tag=amozoniac-20&linkCode=as2&camp=217145&creative=399369&creativeASIN=B003XDTWN2
Basically I am headed south for the winter, but still, last year it got plenty cold many times and my Caribbean bones really needed some heat.