All the techniques are pure whitehat and had zero problems in ranking sites in the Google search engine, plus others like yahoo and bing.
1 - Press Releases Submissions (Paid)
Recently i've been having huge success in using paid press release submissions, i'm currently subscribed to 5 newswires and posting 1 press release a week is having a huge impact in traffic and quick serp increases.
2 - High Pr Manual blog comments
You can't go wrong with manual blog comments, they have huge effects in the serp movements, i'm not talking about small "hey, great blog" comments, i'm talking about actually reading the content of the blogs site and writing a quality response aimed at the blog post or post a reply to a previous comment causing a discussion or argument, which are more likely to get the admin to approve your comment on the blog.
3 - Guest posting
In exchange for posting quality content on other peoples blogs, you can aquire some quality free links that are related to your niche, this is a great way of moving quickly up the serps. Although this takes a lot of time but in the end is well worth the hassle.
4 - Web 2.0 Blogs
Creating web 2.0 blogs from places like webs.com, wordpress.com, by placing totally unique content with 1000+ word articles, which include pictures and a youtube video is working great. Then hitting those web 2.0's with spammy type backlinks from automated programs like xrumer, scrapebox, scrapejet, wiki links etc...
5 - Wiki Links
Still going strong, having some good success posting to wiki links with unique content
6 - Private Blog Network
I don't mean services that are public, when i mean private, i mean PRIVATE! there are plenty of private blog networks about, or even so you can simply build your own private blog network with ease. Buying expired domain names and utilizing there pr juice.
7 -Social Bookmarking
Social bookmarks will always be strong, using these to quickly index your site and also can be great for backlinking your backlinks. Google loves social bookmarking!
8 - Social Signals
Although not a type of backlinking, but with the recent updates, social signals are massively helping with rankings, this can be using facebook, twitter updates, retweets, google plus ones, sending out social signals makes it look like your site has a social buzz and is loved by many people.
9 - Paid reviews
Paying bloggers to review your site can be a huge boost, this looks to google that another blog/website is talking about your site, which helps in serp movements. if your paid review is written unique, it can sometimes drive quite a lot of traffic depending on the reviewer's blog.
10 - Trackback Links
Reward users with trackback links, you will quickly get flooded with links pointing back to your site. A good and quick way of building multiple quality backlinks.
Above are the techniques i'm currently using myself and have had massive effect in ranking in top spots for highly competitive keywords.
I should remind you that, make sure you build links with different anchor text's, do not just focus on using anchors that you are trying to rank for, spreading your anchors around, even if you use your domain name, your site, click here, etc..
I hope you find this post helpful!