I was lucky to start working in database technology since very early - early versions of Oracle (v6), DB2 (2.1 on mainframe), SQL Server (v 6), MySQL (v3), Sybase and Teradata.
Arrival of scalable NOSQL databases and a cloud puts a new life into database technology - what we can do with such databases as Hadoop, Simple DB, MongoDb, Cassandra opens new horizons!
I also start working with Internet technologies very early - sill remember using alpha version of Netscape over PPP and slirp. Was a beta user of Java (still holding SunSoft developer box with the first version of java) and prior to leaving to US (from Israel, mid 1995) was approached by Israeli SUN subsidiary to lead JDBC development (to create JDBC that was not existent at that time).
Using database and java technology while working with large insurance companies (Principal Financial Group, Allied Insurance, Nationwide Insurance), large Internet companies (eBay and Yahoo), supporting major Banks (like SVB) and Casinos (Like WYNN) creates great perspective and knowledge of what is working and not working under very high production load, what architectures are scalable and what is not scalable and should be broken into scalable pieces ASAP and how to handle critical production problems in real time. All this I believe is worth sharing.
I also accumulated huge library of technical tidbits that can be very useful to DBAs, Application Server Admins and well as to System Admins.
Recently I work with data masking technology and find it to be very interesting area to cover as well.
I am sure I'll add more later - but this looks like a good start