Hewlett Packard is currently working on an ARG / Geocaching game and is looking for volunteers. I have played their previous titles and this is legit. If you are interested please check the details below..
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META
Hewlett Packard Labs Research.

Do you enjoy solving puzzles? Are you happy to help with games research? In that case you might be interested in a new game by Licorice Film called "The Sky Remains" (www.theskyremains.com) which will launch soon. The Sky Remains will combine interactive Alternate Reality Gaming elements with mscapes (www.mscapers.com) and the thrill of geocaching and treasure hunting.

We are looking for people who are interested in playing "The Sky Remains" and are willing to be part of a research study to track the experience of using the community web site and playing games over a period of a month. Participants will receive a £50.00 voucher for their involvement for which they will be required to keep a short log of their experiences and be interviewed by the researchers.
Participants will also be loaned an iPAQ for a month so that they can play the mscape games.

If you are interested in helping out and taking part in the research study then please email skyremainsresearch@gmail.com. We are interested in people of all age ranges (over 14) preferably living in the UK.