There is a lot of activity in the online recruiting industry now – more than I’ve seen in many years. Money is flowing in, startups are blossoming, and established players are branching out.

So why now? Part of it stems from the (slow) retreat of the recession – more people working means more interest in finding candidates. Part comes from the rise of social media and mobile, spurring innovation and new thinking about old recruiting problems. And part is dissatisfaction with existing models – more than one of these startups is the result of an industry veteran saying, ‘Hey, I have a better idea!’

Here is my very incomplete list of online recruiting developments and companies that I find interesting (and if you want to see more, check out this fascinating thread on Quora):

• Jobfox Boost: A social media take on the traditional resume database. Allows recruiters to build ‘networks’ of contacts based on their specific criteria – but the real twist is that JobFox will ‘autobuild’ a network from its database of 7 million candidates. Includes a ‘spiff’ option that lets recruiters offer cash for referrals. The sheer size of JobFox’s existing database makes this an immediately compelling product.
• Bullhorn Reach: Similar in some ways to Boost (including the aspirational name), Reach provides a super simple, stripped down way for recruiters to communicate with candidates via social media channels such as Twitter, Facebook, etc. It has two basic pieces: “Jobs”, where the recruiter can create and broadcast a job to her network, and “Radar”, where the recruiter can track, connect, and expand her network. Extremely easy to use.
• VC money: In the past few months, money has flowed into the sector. RoundPegg (matching tool) secured $1.27 million, Glassdoor scored $12 million, InternMatch found$400K,  Entreave (more matching) secured money but wouldn’t say how much, and MyPerfectGig (yep, more matching) landed $3.5 million. That’s just since December. Expect to see more (although, sadly, I doubt any of it will be targeted to job board consultants).
• Zuzu Hire: An interesting approach to candidate screening – offers video, voice, text, and multiple choice screening. Ideal for the company HR exec who just can’t make up her mind.
• JobRooster: Although some job sites have sent job ads via text messaging, JobRooster polishes and extends this idea, adding analytics and the ability to prescreen candidates. In a world where smart phones are not yet ubiquitous, this product makes sense.
• StartWire: In some ways, StartWire flips the traditional ‘recruiter-focused’ product model on its head. Aimed at job seekers, the tool lets them create their own ‘trusted network’ of friends that they can use to find a new job. The company has also promised a product in the near future that attempts to end the ‘black hole’ for job applications. Should be interesting.
• StackOverflow: The well known tech site has implemented one of those ‘why didn’t I think of that’ ideas: peer reviewed candidates. In short, programming problems are posed, candidates respond, and those with their peers vote on the answers. Top vote-getters receive high reputation scores – which inevitably will lure employers. Won’t work in every industry, but a good fit for IT.
• WorkersNow: ERE called it a ‘cloud-based temp company’, and that’s as close as anything. Candidates apply to WorkersNow online, the site screens them, then promotes them to employers. It’s aimed at the plumbers, electricians, and carpenters of the world, and leans heavily on mobile technology. (Also see: ReadyForce)

This is just a taste of what’s happening – I hope it’s given you some ideas about how you can change your own recruiting site!