As soon as i am able to i'll be setting up my mobile "farm", i have nearly 30 phones so far and all capable of around 5Khs so we'll see what comes of it.
30x5khs=150khs. Now you only have to calculate how much power they draw.

And if the phones are free, then you are really lucky. Please post pictures
when your UPX farm is installed. I bet it will be an interesting sight to behold!