Based on my exploits, a guide to "repartition" the N900:

http://sumoudou.org/0/5.html

BEWARE: if you mess up in any single step, you'll brick your N900, and will have to reflash, so not for the meek. You're on your own.

But I did it this way, so it works.

Is there a way to make re-size the 2G app partition to some what bigger than 2G? like 4G i think.

I recognise that site! Wasn't it you who provided a titchy linux image for the HTC Universal there? Hours of fun! Thanks for that! :-)

You could, I think, basically, what you'd need to do is go half way in my guide.

Right at the start where you unmount /home/usr/MyDocs, you'd go into fdisk, remove partition one, create a smaller one, by the amount that you wish to increase the FAT section. Then follow on through.

Then when you go into fdisk later on to change partition 2 to c type, you would first delete this partition and create a new one taking up the whole free space, then follow the rest.

Yeah, it's me

Glad you had fun with the Universal, now let's have much more profound fun with this device...

One thing to test is to overwrite some of the SDK packages with device equivalents. Since you're not booting the chroot it's not as dangerous.

Well, the chroot is fine, I mean I'm using it for compilation as we write now, no probs, and that's all I need it for, and being on the SD there's no space limit...

so you would type all those in the rootsh correct?

Not sure if this would be helpful, but....
I used to have a Zaurus (well, 's still there but dead battery), which had rather limited internal flash memory. To enable users to
a) boot other OS without reflashing,
b) overcome the limit of the built-in memory, and
c) to protect the internal memory from wearing out
they used pivot_root to swap the root fs during boot up to one supplied on a e.g. SD card.
The man page of pivot_root explains the basic procedure...

PS: no N900 here yet, otherwise would have tried it myself.

We use bootmenu here, which afaik does something like that.