wheezy aka testing
64 bits:
wget http://mirrors.kernel.org/debian/dists/wheezy/main/installer-amd64/current/images/hd-media/boot.img.gz
wget http://cdimage.debian.org/cdimage/daily-builds/daily/arch-latest/amd64/iso-cd/debian-testing-amd64-netinst.iso
zcat boot.img.gz > /deb/sdb
## remove/insert usb stick
cp debian-testing-amd64-netinst.iso  /media/Debian\ Inst/
-------
32 bits:
wget http://mirrors.kernel.org/debian/dists/wheezy/main/installer-i386/current/images/hd-media/boot.img.gz
wget http://cdimage.debian.org/cdimage/daily-builds/daily/arch-latest/i386/iso-cd/debian-testing-i386-netinst.iso
zcat boot.img.gz > /deb/sdb
sync

## remove/insert usb stick
cp debian-testing-i386-netinst.iso  /media/Debian\ Inst/


===============
wget  http://mirrors.kernel.org/debian/dists/squeeze/main/installer-i386/current/images/hd-media/boot.img.gz
wget http://cdimage.debian.org/debian-cd/6.0.3/i386/iso-cd/debian-6.0.3-i386-netinst.iso

wget  http://mirrors.kernel.org/debian/dists/squeeze/main/installer-amd64/current/images/hd-media/boot.img.gz
wget http://cdimage.debian.org/debian-cd/6.0.4/amd64/iso-cd/debian-6.0.4-adm64-netinst.iso

#EG usb stick == /dev/sdc

umount /dev/sdc1
#make sure all USB stick partitions are unmounted

zcat boot.img.gz > /dev/sdc

#unplug flash drive and plug back in 

#cp netinstall image to USB stick:

cp debian-testing-i386-netinst.iso /media/Debian\ Inst/

sync

#ready