A couple of days ago Colbird, a developer of the Pro Team, announced that he has managed to get an additional 4MB of RAM out of the PSP 1000 series. This means that if you own a PSP 1000 running custom firmware you will soon be able to join others with some online gaming.
Sorry for my long absence... I've been busy in the Vita Scene (and still am). However I've got some good news for you guys... I've found a way to make Prometheus Online run on 1g units. It's dirty, but it works and gives us 4MB extra RAM on 1g - enough to do online gaming! I will try to update the sourcecode in the near future with some 1g unit compatiblity patches.
Source: prometheus

http://psp.dashhacks.com/2012/08/06/...nline-psp-1000