Recently somebody recommended me this site, http://blogiche.com/, in which you submit your blog, and it will keep rotating your blog automatically (which means no need to click the numbers as it is in BlogExplosion, or EasyHits4U ).
This can easily boosts your daily visitors by roughly 100-200 per day. However, bloggers with Adsense, my advice is please please don't ever try this as Adsense will cancel your account if you enroll in this kind of website, due to a sudden rise in number of impressions. SERIOUS, and they will never reinstate your account again. For others who just want purely more traffic to their website, it may not be a very bad choice. It is FREE and you need to submit your blog everytime you use it.
On the other hand, BlogExplosion, or EasyHits4U provides traffic boost as well, but with the condition that you visit others blog, and you gain credit for others to view your blog. In fact, EasyHits4U can get you a small fortune if you have enough referrals who sured enough sites.
Note: Adsense will not suspend your account if you enroll with BlogExplosion, or EasyHits4U, unless you have violated other rules.