The T-Mobile G1 (also known as HTC Dream) was the first Android device that started the whole Android craze, and apparently, even after years of getting the last official update and now considered pretty much obsolete, it lives once again. The latest version of Android i.e. 4.0.1 Ice Cream Sandwich has been ported to the G1 in the form of an AOSP ROM, thanks to XDA-Developers forum member jcarrz1. So if you had an old G1 that you thought had been revived enough times with Android updates and custom ROMs courtesy of the dev. community, you will definitely want to try this out on your device.
Note that this ROM is currently in its Alpha stage. Being an Alpha version, the ROM surely does have some bugs that need to be ironed out, and while there is a a record on what is functioning and what’s not, the ROM still remains largely untested and is not meant to be used as a daily driver. That said, we’re sure not many of you are using the G1 as a daily driver now anyway, so it can serve as a great pass-time thing to install ICS on this old device and play around with it, rather than letting it catch dust in some obscure spot.
Coming to what’s working and what’s not: touchscreen, Data (unsure), all apps, ICS goodies are functioning properly according to the developer. However, Wi-Fi, Bluetooth and rotation are broken for now. There’s a possibility that you may come across more bugs.
You can also catch a video of the ROM in action on the G1 courtesy of jcarrz1.
It goes without saying, that to install this ROM on your device, your G1 has to be rooted, with a custom recovery installed. The rest of the installation procedure should be pretty much standard – transfer the ROM to your SD card, reboot into recovery, perform a backup, wipe data, cache and dalvik cache, and flash the ROM. So if you want to give it a try, head over to the forum thread at XDA-Developers. Any updates and queries should also be directed there, as being an experimental release, you are likely to come across issues and the community over there would be the best place for finding solutions to those.