[T-Mobile LG G2x] aplsux:
So, I'm writing this post so that there is a unified "thing" for G2X and Linux. I just did this on mine, with information from a bunch of different places, so I'd like to make it easier some people (doing it with a guest Windows machine is not fun).

Thanks to jnichols595, and others.

The procedure itself is painless and quick. For me, everything worked from the first time.

1. ROOTING

* download http://xdaforums.com/attachment.php?attachmentid=577906&d=1303754302

* extract it so it is a folder and cd into it with terminal.

* run the following 1 command:

$ [B]sudo ./root.command[/B]
There appears to be a permissions problem accessing your device
Press Y to try running adb with sudo or any other key to quit: Y
Checking for connected device...
Pushing temporary root exploint (psneuter) to device...
2635 KB/s (585731 bytes in 0.565s)
Running psneuter on device...
property service neutered.
killing adbd. (should restart in a second or two)
Waiting for device...
Remounting /system read/write...
remount succeeded
Pushing su to /system/bin/su...
580 KB/s (26324 bytes in 0.044s)
Pushing busybox to /system/bin/busybox...
1273 KB/s (1062992 bytes in 0.815s)
Installing Superuser.apk android application...
1134 KB/s (196521 bytes in 0.169s)
Removing psneuter from device...
Rebooting device...
Once device has rebooted you should be rooted.
Press Enter when you're ready to quit:

Done, rooted. How do you know? There should be a Pirate's icon in your app menu.

2. INSTALLING CLOCKWORKMOD

* get the nvflash scripts from http://mirror.dal.tdrevolution.net/ctso/g2x/nvflash-recovery.tgz and extract the folder.

* go into the folder and put http://mirrorbrain.cyanogenmod.com/cm/recoveries/recovery-clockwork-3.0.2.7-p999.img in there

* open flash-recovery.sh in that same folder with a text editor and modify the line to say

sudo ./nvflash --bct E1108_Hynix_512MB_H8TBR00U0MLR-0DM_300MHz_final_emmc_x8.bct --bl fastboot.bin --download 5 recovery-clockwork-3.0.2.7-p999.img

* now open terminal and cd into the folder

* remove the battery on the phone, and plug the cable while holding both VolUp and VolDown keys. Hold like that for 5sec and let go

* in the terminal you opened, execute the commans

lsusb

to make sure you see something like this:

Bus 002 Device 008: ID 0955:7f20 NVidia Corp.

* immediately after that, execute the script

./flash-recovery.sh

this is what I had

ibo@ibo-VPCF130FD:~/Desktop/nvflash$ [B]lsusb[/B]
Bus 003 Device 014: ID 0955:7f20 NVidia Corp.
Bus 003 Device 005: ID 046d:c526 Logitech, Inc. Nano Receiver
Bus 003 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 002 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 021: ID 0489:e00f Foxconn / Hon Hai
Bus 001 Device 009: ID 064e:2100 Suyin Corp.
Bus 001 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
ibo@ibo-VPCF130FD:~/Desktop/nvflash$ [B]./flash-recovery.sh[/B]
Nvflash started
rcm version 0X20001
System Information:
chip name: unknown
chip id: 0x20 major: 1 minor: 3
chip sku: 0xf
chip uid: 0x038891c443c145d7
macrovision: disabled
hdcp: enabled
sbk burned: false
dk burned: false
boot device: emmc
operating mode: 3
device config strap: 0
device config fuse: 0
sdram config strap: 0

downloading bootloader -- load address: 0x108000 entry point: 0x108000
sending file: fastboot.bin
/ 1024992/1024992 bytes sent
fastboot.bin sent successfully
waiting for bootloader to initialize
bootloader downloaded successfully
sending file: recovery-clockwork-3.0.2.7-p999.img
\ 4308992/4308992 bytes sent
recovery-clockwork-3.0.2.7-p999.img sent successfully
ibo@ibo-VPCF130FD:~/Desktop/nvflash$

* as soon as some image appears on your phone saying it's updating, you can unplug the phone

Awesome we have the recovery now.

3. Installing the Custom ROM

This one is a video. It is done on a mac, but the computer system does not matter at this point. You just download it to your computer, and then put the zip on the SD card. Use Up/Down to move and Power to select when in recovery mode. This is the guide: http://theunlockr.com/2011/05/03/how-to-load-a-custom-rom-on-the-t-mobile-g2x/

Awesome. Now you can flash ROMs on your device.

***Credits and thanks go to the developers who came up with this, I just put it together!