UK demand for the computer was so overwhelming that its developers said it sold out in minutes and crashed one of the supplier's websites.
Technology commentator Peter Griffin stressed that the computer would have basic functionality - "It's no iPad" - but its size and cost created the possibility of a computer for every child."There will be no excuse for a kid not to have a computer.
"They can put it in their pocket, carry it to school. It's equivalent to what you'd get in an Android smartphone but it costs a fraction of the price.
"Not only does it give kids tools to learn all their subjects, but to also start thinking like software developers themselves so they can pump their ideas out to the world. In the next few years we'll see kids writing their own Android and Apple apps."
Mr Griffin said the product's value was in its bare-bones system, which allowed it to be shipped cheaply and plugged into old, existing technology.
The Raspberry Pi's scale and cheapness were made possible by huge leaps in memory storage in a small space and also a microchip - similar to those in smartphones - which has significant processing power.
A new batch of the Raspberry Pi is expected in four to six weeks, and an even lighter version is expected to be on the market soon. With only one USB port and no ethernet port, it will sell for $30. Some similarly sized, stripped-down computers are already on the market, but the Pi undercuts them on price.
The computer is available here through the nz.element14.com website.
Computer Clubhouse NZ chief executive Mike Usmar, whose company encourages learning by technology, said the product was attractive because it was designed collaboratively - by the industry, teachers, academics and the public.
"That's quite critical because technology shouldn't just be a demarcation between the industry and users. It is not dropping computers out of a helicopter into developing nations - it is about engaging with people and working collaboratively."
RASPBERRY PI
* Retail price: $48
* Size: 85.60mm x 53.98mm x 17mm
* Memory: 256MB
* 2 USB ports, one ethernet port
* No hard drive
* Runs on Linux operating system