^ Like for example this one: http://website.informer.com/forums.digitalpoint.com or this: http://www.alexa.com/siteinfo/digitalpoint.com
I just checked, the link is nofollow. So, no, it doesn't do anything for your SEO. But if your site's ratings are god on those kind of websites (not to confuse with search engines ranking), it's good for you, because people will want to buy advertising from you, write guest posts for you, etc.
hi there, could you please tell me what do you mean by valuation sites .Any ways backlinks always help website but they should from relevant site and good site.(not spammy, with lot of links)
No follow links are good to gain a higher backlinks. It can't help in boosting the rank of your site.
Those are sites that give information about your sites such as page rank, backlinks, estimated site value, etc. Examples: http://website.informer.com/forums.digitalpoint.com and http://www.alexa.com/siteinfo/digitalpoint.com