Getting UPDATEs/INSERTs/DELETEs from transaction log?

I'm doing backup on a second, spare server, by backing up WAL files. I'm
using that server for analysis queries and reporting. Every 15 minutes I
need to shut down that server, place in new WAL files, and restart
server. That is ok, except that I need to backup whole database cluster.
That wasnt't a problem before, but recently another database is in the
cluster, and it's also backed up, although I dont' need it there.

Is there a way (even if it means a hard way?) to somehow extract DML
(except SELECTs, of course, but those aren't ih the log files, right?)
from the WALs, so I can 'replay' it where ever I find it useful?

    Mike