I hear about this PTC offers all the time and I really don't think it is worth the effort and time. IMO, it is better to invest time and dedication to other stuffs. The possbilities of earning online are endless. All you need is a solid idea and the passion to back it up Affiliate marketing is also a good option.
You can make your own website or even just a blog. Get a lot of traffic into it and then monetize it thru a number of ways : PPC, Ad placements, sell text links, sponsorships, etc. Best that you drive in targetted traffic as this has the highest conversion rates.
A lot of big earners on the net started out with simple ideas and put their heart into it and eventually made it big
Attention: "role based name" email prefixes such as support, webmaster, info, contact, forum, service, affiliate, admin, traffic, partners, marketing, etc., for our member accounts are not permitted. They are acceptable for a vendor listing, but not for the member email. This is due to bulk email processors scrubbing them for delivery due to extremely high bounce rates. Please apply for membership using a personalized email prefix. Something like firstname.lastname@example.org.
If we discover you signed up with a role based name we will give you only one message to change it. After 3 days your account will be removed if the email is not changed.