dropbox tool clone

we need a tool like dropbox tool has? 3 components: 1. windows 2008 service that sync file system directories 2. server component, that will be connected by all members and shows the synced directories / files 3. windows vista / w7 client where can sync file system directory or optional only write from server component (but not write any changes back) about 1. windows 2008 service looks continuously for an ini-file, where describes the directories (could have more then one) to be synced the ini files tells the sessions, the allowed windows 2008 services and vista / w7 clients where can connect to this session (and the rights: sync or read only) sync have to work over an ssl http connection files have not to be encrypted (ssl encryption is enough) the service has to write the log to the windows log the service has to handle changed files, very small and large (100mb) files and also stable in case of blocked etc. files sync process has to be be very reactive and fast (even on gprs connections) about 2. server component should be run itself (on a windows 2003 / 2008 server) and have as less a possible perquisites obviously the server component has to be secured (as exposed directly into the internet) and 100% stable the server component has to be able to handle different sessions of windows 2008 services & clients and needs to give a read-only access to websurfers (session / password protected) with an auto-refeshing option about 3. a client like "windows 2008 service" but has? a gui the client connects to a session and allows to define the directory on the client computer optionally the client should bring up a message, in case of new synced files all components have to be developed in c# 2008