[CentOS] Centralised logging with Gui and alerts?

Hi all,

If logging all logs via syslog to a central syslog server that are all Centos based, what GUIs are out there to browse them etc. ? I know about splunk but don't want to go down that route.

Also, some servers are hosted and would be best not sending their logs across the net to a central syslog (although we could openvpn them in), so can the same system be setup to receive logwatch emails?

Any tips or best practices for this above and beyond just a central syslog server would be very appreciated. Server numbers are in the double figures and some are Windows (would be nice to get some of those 'logs' too - snare?).

Thanks.