DNA and brain scans are far from perfect -- you will only get someone "you-ish". In the absence of a solution, you can at least get a bit more you-ness cheaply when the opportunity presents itself. A sufficiently powerful simulation could take all the possible yous indicated by DNA and scans, and see which yous are consistent with the sequences you have saved through screen shots and ect.

It's not perfect, but it should be a little bit better.

Even better would be if you did something more complex and less externally guided than web-browsing... write a book, a blog, or a song. Also, save your LessWrong username in that file!