Hehe I dont think learning them all is smart, I rather learn what will be relevant else you'll be studying your whole life and you'll have to keep up to date with all the languages.
I choose, well I dont know how to really call it, but I choosed grouped languages to learn:
1e group: (X/D)HTML, CSS, PHP(5), MySQL, tiny winy bit of JavaScript
2e group: ASP.NET C#(website), JavaScript, C#(programs), MSSQL(incl. Stored Procedure), webservices(not a language, but he
)
3e group: JAVA, XML, JSP and PostgreSQL(incl. Views)
The languages in a group are most relevant to each other (of course you can use it separated or in combination with a other group). And the languages in 1e and 2e groups I have most knowledge about.
The funny part is I learned all the languages in groups in different places:
1e group in school, 2e group was internship and 3e group my job (wich I am currently most active in)
The only last language I have a interest in is Python, because of the good words off the Django framework.
So niecah, pick your choice