Netbooks are generally the smallest "laptops." But they vary from different brands such as Acer, Asus, HP, etc. So I would choose a name I'm familiar with or have heard great things about and try to find one suitable to you and your price range.
The smallest laptop on the market is called the Foleo. It is bigger than a smartphone, but smaller than a regular laptop. The Foleo is not considered to be a netbook.
The smallest laptop Apple produces is the MacBook. It is measured at 13 inches.
Commonly known as a netbook.
If you are looking for a smallest laptop. I suggest Mac books, they are really lightweight and portable. They are also fastest performance and great graphics. It is great for school or any personal use.
According to the information on the internet the Sony Vaio S series laptops has the smallest laptop in their collection. The smallest laptop has a 8 inch wide screen display and only weighs 1.4 pounds.
The Sony Vaio's can be availed in the smallest size the smallest being 11.1 inches in the TT. It is also available in pink apart from many other colours.
The optimum size for a mini laptop screen is 7". This is the smallest size for a mini laptop and they range in sizes from there. You can always visit a store to find out about other sizes.
"The question doesn't state whether if it wants me to answer the about the weight or about the price, so I will answer to both. The lightest laptop out there is about two point five pounds. The cheapest laptop out there is worth about two hundred dollars."
With the rapid rate of production of new laptops and electronics the smallest I could find presently is the Sony Vaio S Series laptop. Starting at almost $900 it is a big price for a little item.
One of the smallest and lightest laptops is the UMID mBook M2. It weighs less than a pound and has a 4.8 inch display. The Asus Eee PC T91MT Tablet is just a little bit bigger than the mBook.
I think that is the Altec Lansing FX2020 Expressionist Classic Speakers, they are tiny.
Right now, the smallest laptop that you can buy without going into the I-pod category would be the 5 inch. This is not so good for videos, but has been proven great for college aged kids using it mainly for note taking and for surfing the web for homework, games, etc.