One of the great ways to build a referals in other traffic exchanges and programs is through the use of downline builders.  A downline builder really advertises multiple programs and as people signup with the downline builder they are placed under you in all the programs they join.  The great thing about downline builders is that you can focus on promoting the downline builder and watch your referals grow.
TrafficHoopla - Very similar to Vital Viral, but contains a number of different traffic exchanges, so it expands your ability to build your downlines.  I like TrafficHoopla because they take an educated approach to building downlines in their promotion pages.  Give it a try.
FreeViral - This is not exactly a downline builder, but it does accomplish the same thing in that people sign up to add their link, but they must view 6 other websites on their way to getting their link shown.  Oh, and did I mention this is completely free.  You do need to promote the link, but it has such a huge potential to generate visitors you need to make this part of your marketing arsenal.
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The Marketing Pond - Maybe the only downline builder you will ever need.  This downline builder has so many programs that help you build that massive downline, and many of them can earn money for you while you are promoting the Marketing Pond.  There are paid to read, paid to click, traffic exchanges, other downline builders, and the list goes on an on.  In fact it will take you a couple hours just to sign-up for everything, but it is well worth it.
Traffic Digger - Very similar in concept to FreeViral where you advertise one program.  When someone joins traffic builder they must click on your advertisement, and in turn when they promote Traffic Digger your business opportunity shows up on their list.  Another very good viral method for advertising.
T-2000 - Another viral downline builder similar to FreeViral.  Use this in conjuction with FreeViral and Traffic Digger, and you can really amp up your advertising efforts.
JoeSacco.com - Your source for Internet Marketing Tools and Opportunities
Vital Viral - Their back!  Yes my favorite dowline builder is back.  This is not just another downline builder because it actually pays commissions when someone upgrades to premium status.  In fact if you are a premium member yourself you get a 40% commission.  So in addition to being a great downline builder you can actually make money from it.  Pretty cool!