Here are 101 social bookmarking sites that have dofollow links and do pass some Google juice one way or the other to the listed sites. Let me warn you that these are not effective if your link building campaigns ends with only these, but they are nevertheless worth a try.
Pagerank 9
http://www.technorati.com 694
http://www.slashdot.org 1,605
Pagerank 8
http://www.reddit.com 574
http://www.mixx.com 854
http://www.propeller.com 2,027
Pagerank 7
http://www.metafilter.com 2,451
http://www.wikio.com 3,331
http://www.care2.com 3,190
http://www.folkd.com 4,098
http://www.connotea.org 8,197
Pagerank 6
http://www.dzone.com 3,836
http://www.sphinn.com 4,945
http://www.linkagogo.com 11,499
http://www.kirtsy.com 16,850
http://www.tipd.com 23,528
http://www.kwoff.com 24,261
http://www.bloghop.com 31,217
http://www.weheartgossip.com 32,225
Pagerank 5
http://www.indianpad.com 3,185
http://www.spotback.com 11,391
http://www.mylinkvault.com 12,748
http://www.buddymarks.com 13,857
http://www.plime.com 18,583
http://www.designfloat.com 22,384
http://www.web2list.com 23,051
http://www.fcc.com 37,050
http://www.linkatopia.com 40,811
http://www.iliketotallyloveit.com 42,754
http://www.japansoc.com 60,200
http://www.buzzup.com 68,384
http://www.scoopit.co.nz 91,077
http://www.ngopost.org 94,741
Pagerank 4
http://www.humsurfer.com 1,321
http://www.a1-webmarks.com 10,230
http://www.oyax.com 11,312
http://www.socialogs.com 19,806
http://www.quadriot.com 22,255
http://www.blurpalicious.com 22,742
http://www.wagg.it 23,275
http://www.uvouch.com 24,122
http://www.blogmarks.net 24,989
http://www.maple.nu 27,330
http://www.mysitevote.com 33,282
http://www.blogbookmark.com 33,810
http://www.blogengage.com 38,085
http://www.pageactive.org 40,026
http://www.totalpad.com 47,978
http://www.solinkable.com 48,485
http://www.graphic-design-links.com 52,491
http://www.justpoint.org 55,067
http://www.indiareporting.com 60,218
http://www.feedmarker.com 67,554
http://www.pfbuzz.com 83,239
http://www.websapiens.net 86,767
Pagerank 3
http://www.bookmarkindo.com 22,953
http://www.wobblog.com 23,482
http://www.yattle.com 23,572
http://www.diggdirect.com 23,645
http://www.th3scoop.com 24,459
http://www.oopza.com 26,962
http://www.koolontheweb.com 27,576
http://www.tedigo.net 34,851
http://www.memfrag.com 44,021
http://www.bringr.com 49,065
http://www.sweepsgoat.com 67,278
http://www.haohaoreport.com 69,869
http://www.yuppmarks.com 102,929
http://www.craftjuice.com 105,996
Pagerank 2
http://www.bestofindya.com 16,005
http://www.newscola.com 24,055
http://www.gaddiposh.com 27,155
http://www.cmymark.com 30,432
onlinesocialbookmarking.com 48,552
http://www.cadillactight.net 48,717
http://www.spotonce.com 52,054
http://www.uan.me 53,345
http://www.xmaui.com 58,140
http://www.gyach.com 74,729
http://www.ziki.com.au 76,369
http://www.i89.us 76,369
http://www.spicybookmark.com 77,033
http://www.jackool.com 78,621
Pagerank 1
http://www.topstumbles.com 30,120
http://www.bookmarkplace.com 33,543
http://www.indianpick.com 44,892
http://www.starton.us 48,868
http://www.brightsapphire.com 50,763
http://www.gadgetsieve.com 51,005
http://www.iorkut.net 54,051
http://www.wedelia.com 57,128
http://www.bookmarkglobe.com 71,369
http://www.hitmarks.com 78,367
http://www.webpics.info 78,691
http://www.myfavlinks.com 81,902
Pagerank 0
http://www.indianbytes.com 17,991
http://www.earthfrisk.com 22,917
http://www.dekut.com 26,427
http://www.blogreporter.biz 34,513
http://www.kapely.net 47,889
http://www.under-link.com 83,861
http://www.mecozz.com 89,355
http://www.seedz.org 97,789