I'm so sleepy.
The reddit thread will prob have more action
We've already caught and fixed a couple bugs (we were having issues when an address had a nonce of 0) so please give it a go with a small amount first.
This is a way to generate offline transactions from beginning to end. The process happens in three steps.
1. Use an online computer to generate the gas price and nonce.
2. Use an offline/airgapped computer to enter add’l information, along with your private key / JSON file, and generate a signed transaction.
3. Move that signed transaction to an online computer.
Obviously, you could use this process entirely online in order to send data with your transaction and/or increase the gas limit.
If you already know how to generate a transaction in another way and just want to bring it online, you can paste it in the third step and bypass the first 2.
Please test it out and let us know if you get errors, where you get these errors, what is confusing, etc. It took me a couple tries to get a transaction to go through. This certainly isn’t easiest thing.
If you would like to send a message in the data (like I did above) you can do so by using an ascii->hex site like this to generate a message. Just type your message, copy the hexadecimal output, and then remove all the spaces in that hexadecimal output. You will need to increase the gas a bit (it was 23,040 for the short message "myetherwallet.com is the best" and will be more for a longer one).
Lastly, it's now 2:15am and we're going to bed. We will reply to comments in ~5.75 hours when we wake up to go to work. Thank you for understanding.