Bean Bags

B&H has a page of bean bags that can be draped over an open car window, and some which attach to the tripod socket or with straps. I've used the latter in various public and private attractions where tripods weren't allowed. Mine came filled with plastic pellets. Sand is too heavy, bird shot heavier yet. Real beans and rice work, but are subject to agricultural inspections, confiscation and fines if you cross certain borders.

http://www.bhphotovideo.com/c/search?Ntt=bean+bag&N=0&InitialSearch=yes&ipp=50

If you're traveling and want to avoid extra weight, get a bag made/sewn with a zipper and some plastic bags for liners, and you can carry it empty and fill it with beans, gravel, or whatever you can find in your destination.
In a real pinch, buy a bag of beans at a local market, discard when you leave. It don't cost beans to do so. ;)

Sanjay,
I frequently use a similar product without the mounting screw for a head. I keep it in the car filled with sunflower seeds. I am sure that you will find some who will say that it is better for one reason or another if the camera/long lens is on a ball head or other mount. I simply am not of that camp. I often frequent wildlife reserves which have rather long "drives" and I just roll the window down set the bean bag over the door and rest my 500mm lens on the bean bag. The elevation is nearly perfect and the bean bag holds the lens plenty still. If I need to get out and use the bonnet or the boot I just flip the bean bag over, and in the event of a sudden rain or gust of dust I just set the cam on the seat beside me pull the bean bag and roll up the window.
When driving, (SLOWLY), through the preserve I can leave the lens hanging out and rest my hand on it gripping the mounting foot which I invert for this purpose. I have lots of great shots thanks to my bean bag.

You really have to buy a commercial product?
Making a bean bag for a rest is pretty simple and easy to do.

Hi, I am looking at the skimmer sack beanbag from naturescape . Is this good and is the skimmer ground pod of any use? I might get a 600mm lens in future (not sure how many years down the lane ). How is the wildlife imaging beanbag and is the fat bag from kirk good?

thanks in advance

I am narrowing it down to the skimmer and wildlife imaging bag. The skimmer as they say it can handle the 600mm and has straps too. thanks once again and wish you all advance merry xmas.

The lightweight Puffin Bag (B&H website) looks appealing - i.e., after trying a number of commercial and "homemade" varieties. The last thing I want now is to carry another heavy gadget in addition to the metal camera equipment.

I use the Molar Bean Bag. It's Built like a Tank. I use it whenever I am shooting from My Vehicle.
I used dried navy beans. the only down side is the weight,I would discourage anyone from raising and Lowering with the bag and camera. Its Rock solid,I know several Guys that use them with 200-400's 500mm and 600mm lenses.

Thanks all. Can I use the beanbag on the side of the jeep on the frame ? I went for a safari in an open jeep with two doors and the back is completely open from seat level onwards . In this case, I would have to rest the lens on the jeep frame next to the front door.