Internet marketing has expanded into yet another channel in recent months as a few startups are attempting to tackle the world of Twitter marketing. From the beginning, companies have used Twitter as a PR outlet to announce updates, offer coupons and deals, and connect with followers. The San Francisco Chronicle reports, however,  that in the last six months a few startups have now ventured into Pay-Per-Tweet marketing, where companies have reportedly paid celebrities between a few dollars and $10,000 to tweet an ad for the company.  Similar to PPC search engine marketing, firms are then paid per click-through.

With celebrities having upwards of 1.5 million followers and growing, Pay-Per-Tweet marketing could be a great way for companies to reach a targeted audience. How profitable it is for the advertiser remains to be seen.