[mixmasteralan]

103 characters with native js:

d=document;f='getElementById';d[f]('mw-sopaOverlay').innerHTML='';d[f]('content').style.display='block'

[mixmasteralan]

In 42 characters!

l=location;l.href=l.href.replace("en","m")

[mixmasteralan]

In 35 characters! location.hostname="m.wikipedia.org"