Cisco Packet Tracer - I downloaded this software for free from Cisco. From the name "Packet Tracer", you would think this is some type of packet capture/analysis tool similar t...
All things Java seemed up there on the list. You should learn Hibernate. Know your JSPs. Even old school Java technologies such as JDBC can help you get a good salary. And of course app servers like jBoss can give you a kick up in pay.
I am hearing more and more about DevOps. Not quite sure I get it yet. But knowing Puppet, Chef, and Jenkins can put you in the running for a lucrative career.
Then there is the Hadoop corner. I don't know all the details. But good buzzwords are Hive, Pig, and Hbase. Heck. Even the base technology of MapReduce is still a desired one by employers paying the big bucks.
Finally there is the noSQL camp. Turns out Cassandra is one of the hottest implementations of a noSQL database out there. Hot trends are always changing. But it is good to try to learn a thing or two in the hot sector.