If you are looking for an alternate to blog commenting with your links+keywords, try to use Profile-Styles sites where HTML/BB Code can all be instantly copied in the About Me Page or Bio box. Most of these sites are DO-FOLLOW and can drastically boost your SERPs rank.

HTML Set Up:

<a href=”http://www.yourdomain.com”>Your Keywords</a>

BBCode Set Up:

[url=http://www.yourdomain.com]Your Keywords[/url]

Textile Set Up:

“Your Keywords”:http://www.yourdomain.com

50 sites with About Me-Profile page:

http://www.rottentomatoes.com/  Page Rank 7
http://urbis.com/  Page Rank 5
http://www.movieweb.com/  Page Rank 6
http://www.myheritage.com/  Page Rank 6
http://wegor.com/  Page Rank 4
http://www.celebuzz.com/  Page Rank 6
http://www.2threads.com/  Page Rank 6
http://72photos.com/  Page Rank 4
http://www.recipezaar.com/  Page Rank 6
http://vetrinas.com/  Page Rank 4
http://www.mychurch.org/  Page Rank 5
http://www.blogged.com/  Page Rank 6
http://drop.io/  Page Rank 6
http://www.blipfoto.com/  Page Rank 4
http://www.indie911.com/  Page Rank 5
http://www.zenfolio.com/  Page Rank 5
http://www.thepoint.com/  Page Rank 6
http://www.cutcaster.com/  Page Rank 4
http://www.winelog.net/  Page Rank 5
http://www.visualcv.com/  Page Rank 6
http://www.tasteofhome.com/  Page Rank 7
http://www.spreadthunderbird.com    Page Rank 8
http://www.comedycentral.com/  Page Rank 7
http://www.bleedyellow.com/  Page Rank 4
http://www.bakotopia.com/  Page Rank 6
http://www.teenspot.com/  Page Rank 5
http://www.onemanga.com/  Page Rank 6
http://www.watzatsong.com/EN/  Page Rank 4
http://www.urbanryders.com/    Page Rank 4
http://www.burntmarshmallows.com/   Page Rank 5
http://www.trailfire.com/   Page Rank 5
http://www.eyejot.com/   Page Rank 5
http://www.communitywalk.com/    Page Rank 6
http://www.gravee.com Page Rank 5
http://openkapow.com/   Page Rank 4
http://www.reasonproject.org/  Page Rank 5
http://www.adegga.com/ Page Rank 5
http://www.hackint0sh.org/forum/  Page Rank 5
http://www.bigadda.com/   Page Rank 5
http://www.thenakedscientists.com/forum/   Page Rank 7
http://craversclub.com/forum/index.php    Page Rank 4
http://www.sosblog.com/  Page Rank 5
http://www.googlecommunity.com/   Page Rank 5
http://forum.civicrm.org/   Page Rank 6
http://www.magentocommerce.com/   Page Rank 8
http://planet.betterplace.com/   Page Rank 6
http://community.mcafee.com/   Page Rank 4
http://www.izania.com/   Page Rank 5
http://www.redefinegod.com/   Page Rank 4
http://www.revish.com/   Page Rank 5
http://triptie.com/   Page Rank 4

The sites above are just some of the hundreds and thousands of web 2.0 sites where you can leave a profile backlink. Try to expand it and search for yourself.