I just tested them all on my DS2413+ and here are the Cedarview packages available from the working repos:
http://packages.synocommunity.com
BitlBee, BitTorrent Sync, COPS, SouchPotato Server, CouchPotato Server Custom, DarkStat, Debian Chroot, Feng Office, Full-Text RSS, GateOne, Git, HAProxy, Headphones, HTPC-Manager, LazyLibrarian, LIRC, MantisBT, Maraschino, Memcached, Midnight Commander, Mylar, NZB Config, NZBGet, ownCloud, Python, Redis, Roundcube Webmail, SABnzbd, Selfoss, Sickbeard, Sickbeard Custom, Subliminal, Tiny Tiny RSS, Transmission, Tvheadend, uMurmur, ZNC
http://packages.synocommunity.com/?beta=1
BicBucStriim, Disk Utils, ejabberd, FlexGet, Horde, jappix, Mutt, Newsnab, NZBGet Testing, NZBMegasearcH, Python3, Ruby, ruTorrent, SquidGuard, Subversion, Vim, XDM
http://packages.missilehugger.com
Funambool, Java SE Embedded, MediaInfo, Openfire IM Server, Shellinabox, Web Console, YAMJ
http://packages.pcloadletter.co.uk
Bliss, Craftbukkit, CrashPlan, CrashPlan PRO, CrashPlan PROe client, CrashPlan PROe server, Java SE Embedded 6/7/8, Minecraft, OpenRemote, Serviio,
http://e-remonty.info/spkrepo/packages
OpenKM, Owl DMS, SMS Orange, SMS Plus, Squid, Webcam 4.1/4.2/4.3
http://www.cphub.net
Advanced Power Manager, autorun, BubbleUPnP Server, Cronjob editor, DDNS updater, Growler, Init 3rdparty, Init 3rdparty Help, iPKGui, MailStation Plus, MLDonkey, Multi-IPX800 Server, MusicIP Server, net2ftp, Noitification Essentials, Notification Forwarder, Notification Messenger, OwnCloud, PHP Net_Growl Library, phpMyBackupPro, phpPgAdmin, Plugin VideoStation FR, Rootkit Hunter, Serviio Console, SQL Buddy, String Editor, Subsonic, Subsonic-backup-creator, Synology Monitoring Tool, traccar, tvstreamrecord, Webmin
http://synopkg.superzebulon.org/spkrepo/packages
CouchPotato, Headphones,
http://synology.mdevries.org/spkrepo/packages
Auto-Sub Bootstrap Bill, CouchPotato, Gamez, JSMusicDB, LazyLibrarian-1, MovieGrabber, PlexConnect, SicBeard ThePirateBay, SpotWeb, TraktForBoxee, XDM
http://synology.sysco.ch
Synology Monitoring Tool
http://cytec.us/spk/
ffmpeg, Headphones Custom, Node.js, PlexConnect, Pydio, SynoDNLAtrakt, Webogram
http://synopkgs-garble.rhcloud.com/
Static Photo Gallery, SynoMiner
https://www.christoph-papke.de/spkrepo/spkrepo/packages
Syno PHP Auth
http://spk.naefmarco.ch/spkrepo/packages/ Mirror: http://spk.nas-mirror.de/spkrepo/packages
AutoIndex, BBClone, FSyncMS, Midnight Commander, Network UPS Tools, SPK-Repo
http://subtitlessh.no-ip.biz/repo_spk/
SubtitlesSH: Download subtitles for movies
http://synobox.fr.nf/synopackages/ - http://synobox.fr.nf/synopackages/beta.php
Dropbox Client for Synology
http://repo.synozwave.com/
Open Zwave: Home Automation
http://spk.unzureichende.info/
MiniSAPServer, pyLoad, udpxy