[jQueryIsAwesome]

Don't use unescape, is ugly and is not required if you break the close tag of "script".

    this.jQuery||document.write('<script src="js/jquery-1.8.3.min.js"></sc'+'ript>')

[crescentfresh]

Yes, also document.write('\x3Cscript>\x3C/script>'). But these are beside the point.

[jQueryIsAwesome]

Well; I also think this is going offtopic but I have to mention "unescape" is not a JS standard but it is available in most JS engines; in the other hand literal Unicode codes in strings are part of the ES specification.