As usual at Christmas, there is a lot of talk about what will be this year's must have toy. Toys such as Elmo Live by Fisher-Price are, as you would expect in many experts prediction list. This year however, the crown of most wanted toy may not go to any of the well established multi-nationals. Instead this year the most wanted Christmas present may be the intruding R4 for Nintendo DS.

R4 unlocks the ability for a DS to read from an SD card. This opens up a whole load of possibilities. One of these is that the Nintendo DS will now be compatible with homebrew applications which can be stored on the SD and inserted into the R4.

Since the R4 gives its users so much potential to use their DS in lots of new ways, it has been seen creeping up the Amazon best sellers lists. Although it will probably not be on the news as the best selling toy of Christmas as it is not stock in high street stores yet, it could be facing stock problems like all the best toys.

An example of the type of application available for the R4 is DSOrganize. This piece of software allows you use your DS as a basic office suite. It includes a file browser, web browser, text editor, image editor, calculator, calendar, contact list amongst other useful features.

Moonshell is an operating system for the R4 which lets you browse homebrew applications as well as integrating an MP3 player, video and photo viewer. There are several operating systems available but Moonshell is the most popular.

The R4 even lets people stay in touch with their friends and family. Homebrew applications allow users to connect to their MSN, AIM or yahoo messenger. Most interestingly of all, Skype can also be used with the R4. This means that a DS can pretty much be used as a mobile phone as long as a Wi-Fi connection is available.

DSLibris enables the DS to display ebooks, turning the machine into a small library of books for you to read at your pleasure. DSVNC can be used to control a PC. DS Boro is a web browser. The list of new ways to use a DS with an R4 goes on.

Nintendo really missed a lot of potential for the DS originally by not including a flash drive as the PSP has. The R4 has fix that problem but Nintendo are keen for to have people use their own device for reading flash card, so they have introduced a new model of DS, the DSi.

The primary reason for the flash reader in the DSi is to store photos taken on the DSi's new cameras and music files. It seems unlikely that Nintendo will allow homebrew applications to be ran through the DSi without an R4 as Nintendo have a history of strict control over what is released on their systems.

Nintendo's strict controls possibly steam from the early 80s when the video game market was in decline due to a large amount of poor quality games which flooded the market. In response to this, the Nintendo Entertainment System was the first console to include a chip which prevented games being manufactured without Nintendo's approval.

This however took away from consumer choice. The R4 brings this choice back.