Here is a SMALL Twitter-clone/twitter-like sites collection

From German
http://www.wamadu.de
http://www.frazr.com
http://www.faybl.de/
http://www.partnr.de/
http://www.texteln.de/
http://www.familyone.de/
http://www.1you.de
http://www.sloggen.de/
http://www.slogr.de/
http://www.dasbeep.de/
http://www.baluuu.net/
http://mambler.de
http://www.brabblr.com/
http://www.dukudu.de/
http://www.plappadu.com/
http://www.pownce.com
http://mambler.net
http://boomloop.de
http://www.yoyolog.de
http://www.pacmee.com
http://www.was-geht-bei-dir.de

From Japan
http://timelog.jp
http://mogo2.jp
http://haru.fm/
http://www.nowa.jp/
http://www.feecle.jp/
http://gree.jp/
http://chat.doovii.com/
http://tsublog.excite.co.jp/
http://wassr.jp
http://piyo.fc2.com/
http://frepa.jp/
http://weime.jp
http://cotobaco.com/
http://himatch.net/
http://c2.koukokukaigisitsu.com/
http://iddy.jp/
http://www.excite.co.jp/
http://aboutme.jp
http://h.hatena.com/
http://imachu.jp/

From China
http://komoo.cn/
http://byuu.com
http://jiwai.de/
http://www.fanfou.com
http://wulog.com
http://buboo.tw/
http://www.ingbus.com
http://fish.sh
http://www.laigula.com
http://www.zuosa.com
http://ilaodao.cn
http://www.9fav.com/
http://vikooo.com/
http://www.taotao.com/
http://www.mangfou.com
http://laodao8.com
http://5uie.com/
http://17xw.com
http://www.redekuai.com
http://www.ingzzz.com
http://shuo.in/
http://www.ilaosao.cn/
http://ledao.in/
http://www.missui.com
http://www.shuoxiu.com/
http://www.jigugu.cn/
http://www.iliaoke.com
Chinese Twitter-like sites:
http://weazone.com/
http://popwu.com/
http://www.v2ex.com/ing
http://bulo.hjenglish.com/ing
http://www.atnote.com/
http://www.rizuo.com/
http://www.life365.com/
http://video.qq.com
http://www.qianne.cn
http://ondream.org
http://www.qooqer.com
http://www.qianne.cn/
http://www.3user.com
http://show.msn.com.cn/
http://www.9fav.com/
http://phottor.com/
http://goofy2.com

From English,Italiano and Francais speaking countries
http://www.hictu.com (English,Italiano,Francais)

From Spain
http://www.twilove.com
http://www.trikir.com/
http://khaces.com/
http://fritsi.com/
http://miniblog.20minutos.es

From Poland
http://www.robisz.pl/
http://moblo.pl/
http://pinger.pl/
http://blip.pl/
http://plom.pl/
http://flaker.pl/

From France
http://noumba.net/
http://www.iratemyday.com/
http://oseflol.com/
http://www.blogitexpress.com/

From Korea
http://me2day.net
http://playtalk.net

From USA
http://www.bebo.com/
http://skittr.com/
http://www.moodmill.com/

From Dutch
http://www.kwid.nl/
http://numpa.nl
http://zezz.nl
http://babl.nl/
http://qmsg.nl/

from Indian
http://webaroo.com/
http://snockles.com/
http://www.kwippy.com

from Hungary
http://pzn.csacsa.hu/
http://www.chatter.hu/
http://tothbenedek.hu/turultwitter/
http://www.mitcsinalsz.hu/
http://mitcsinalsz.hu/
http://turulcsirip.hu/

from Russian
http://www.mmm-tasty.ru
http://smspr.ru/
http://edno23.com/

from Indonesia
http://www.kronologger.com

from Rumania
http://www.cirip.ro
http://www.logoree.ro

from Portuguese
http://www.gozub.com

from Turkey
http://nolyo.com/

from Mexico
http://mexicodiario.com

From Singapore
http://tiish.com/

From Czech
http://drbz.cz/

and more……
http://www.jaiku.com/
http://www.moodmill.com
http://blogthot.com
http://pulse.xanga.com/
http://www.blogthot.com
http://yelago.com
http://www.viwio.com/
http://www.jaxblog.com/
http://yappd.com/
http://fritsi.com/
http://www.blabto.com/
http://www.wowwao.com
http://zaxino.com
http://niimo.com
http://www.zannel.com
http://noumba.mcm.net/
http://www.emotionr.com
http://www.reise.tk/
http://miniblog.20minutos.es/
http://www.intuuch.com
http://twoggle.com/
http://www.zwitti.com/
http://www.yurbo.com
http://www.sweetter.net/
http://www.bloggino.com
http://www.chittr.com
http://boobik.com
http://foodlily.com
http://www.mobicue.com
http://www.blogynet.com/
http://www.snappler.com/
http://www.yonkly.com
http://www.fyreball.com/
http://yootag.com/
http://microblogr.com/
http://cromple.com/
http://watwet.com/
http://www.anywr.com/
http://www.plurk.com/
http://adocu.com/
http://twoorl.com/
http://cliqck.com/
http://talkaboutadate.com/
http://www.yousaytoo.com/
http://www.peyghamak.com
http://www.rememble.com
http://www.talk.org
http://zobzee.com/
http://www.enqando.com/
http://bynotes.com/
http://www.ingamenow.com/
http://blip.fm/
http://fazkut.com
http://www.mytalk.at
http://dandelife.com
http://jisko.net
http://identi.ca/
http://rejaw.com/
http://plerb.com/
http://www.koornk.com
http://www.bimbl.com
http://fidj.it/
http://gospelr.com
https://www.yammer.com
http://bloggy.se/

Twitter-like sites
http://www.shopalize.com/
http://gatsb.com/
http://www.radar.net/
http://www.yelp.com/
http://www.meshly.com
http://www.kyte.tv
http://www.phonetagit.net/tstart.aspx
http://www.spinvox.com/
http://panraven.com/
http://www.letmeparty.com/
http://www.mysay.com
http://jott.com/
http://hahlo.com
http://www.nowthen.com
http://www.gluenow.com/
http://www.feedxs.com
http://loopnote.com
http://plusmo.com
http://www.tiggdo.com/
http://www.seesmic.com/
http://zaptxt.com
http://www.blogarithm.com/
http://immedi.at/
http://www.anothr.com
http://www.yatam.com
http://kotonoha.cc
http://bravetrail.com/
http://www.groovr.com
http://personalinfocloud.com/
http://atara.cc/
http://www.frengo.com
http://www.cubevoice.com/
http://www.beemood.com/
http://www.poodz.com/
http://www.funpiper.com
http://beta.vooeasy.com/
http://www.controlc.com
http://www.twitxr.com/
http://www.blogozavr.com/
http://hakatter.com/
http://www.thingfo.com
http://placeshout.com/
http://www.poodz.com/
http://liveshouts.com/
http://keepdream.com
http://foodfeed.us/
http://www.podobo.com/
http://www.ventbox.com/
http://floort.com/
http://www.suggerus.com/
http://www.wazzupnow.com/
http://help.com/
http://www.kazivu.com
http://www.fuzz.com/blip
http://www.locify.com/
http://sweetter.net/
http://brightkite.com/
http://tapioka.ca/
http://ticketapp.com/
http://p0pulist.com/
http://moonri.se/
http://www.mojipage.com/
http://www.globme.com/
http://www.mixin.com/
http://www.blippr.com/

multiple posting
http://hellotxt.com/
http://www.presencr.com/
http://www.brabblr.com/
http://twitku.com/
http://www.feedlr.com
http://ping.fm
http://shoutoo.com/
http://vibstars.com/
http://www.syncbus.net/
http://updating.me/
http://pikchur.com/

open source microbloging services
http://www.revou.com/
http://www.folkstr.com/
http://www.gelatocms.com/
http://chyrp.net/
http://twoorl.com/ an open source Twitter clone,Get the source code
http://smob.sioc-project.org/
http://sweetter.net/
http://laconi.ca/
http://jisko.net
http://identi.ca