READ FIRST PLEASE!!!!!
the devteam has released a tool for jailbreaking and unlocking the iphone 3.0 firmware, this works just in the iphone 2g, ipod touch 1st and 2nd generation, but it doesnt work on the iphone 3gs. and it doesnt unlock the iphone 3g, it just jailbreaks it. if you want to unlock your iphone 3g you will need to wait for “ultrasnow” witch will be released soon.

here are the instructions to jailbreak/unlock the 3.0 firmware.

download your firmware for your device.
iPhone 3G:
iPhone 2G:
iPod Touch 1G:
iPod Touch 2G:

then download redsnow.
redsnow for mac
redsnow for windows

then download the bootloaders here if you dont have them. extract them with winrar for windows, or the unarchiver for mac.

open your itunes 8.2, detect your iphone and click on restore as you press shift. in mac, press and hold alt when you click restore.

choose the firmware that you downloaded in step 1 and wait for the iphone to be restored.

your iphone will reboot and will be locked. dont worry, its time to use redsnow.
open it, and browse for the firmware that you have downloaded.
check options install cydia and unlock if you want.
if you want to unlock your iphone 2g, you will be asked for the bootloaders that you downloaded in the first steps. browse for them.
now, redsnow will ask you to turn off your iphone.
follow the instructions to have it on dfu mode.
now redsnow will do its work. you are done.

if you have any questions, in the comments please

Finally apple is going to release a decent iphone firmware. With the iphone 3.0, you can copy & paste, you can use bluetooth for some things, you can send mms, and some other things.
Dev-team has said that the iphone 3.0 firmware is unlockable, you can jailbreak it, or unlock it, but they wont release a tool to do it for now until its officialy released. They just give one advice, dont upgrade your iphone 3g with the firmware 3.0, because it will update the baseband and the yellowsnow app will be useless. Be patient and wait for a custom firmware or for a newer version of yellowsnow.
When the iphone 3.0 is released, i will post here step by step, how to upgrade your iphone to the 3.0 firmware, and how to unlock/jailbreak it.

update: the iphone 3g s is going to be released on 17/6/09. When the dev team posts a guide to unlock it, you will find how to unlock the iphone 3g s here.

We are closer to have in our hands an app to transfer music, photos, etc with your friends cellphones via our apple iphone. medevil has posted a video where he shows how he can transfer files via bluetooth to a mac and a sony ericsson. Also there is an app, sweetooth, and their developers are working on it to get it finished. we are going to have bluetooth unlocked too soon guys!!

We are starting the 2009, and we have started it with great news. You can unlock your iphone 3g noW!!
its a beta release, but if you are interested, i have posted the guide step by step here:
how to unlock an iphone 3g

Mobile cinema is a very buggy app that works with jaibroken iphones. it works most of the time, you need to have a 2.x iphone firmware. This app will give you flash support in websites with flash in safari.
Well this is good news, there is just one thing missing, the bluetooth, hackers.

Add this to your cydia sources: d.imobilecinema.com
install mobile cinema

Read again, this just works with jailbroken iphones.
This app is still very crashy, hope that developers can fix all the bugs in the app soon.
This is like a flash player, it works most of the time.
Any question, in the comments please!