This makes a 4GB file when decompressed and is plenty large enough to crash a 32-bit browser. You may need a larger file to reliably crash 64-bit browsers.
Haven't tried it, but does it crash the browser or the tab? Under Chrome's architecture, a page should potentially be able to crash the tab, but not the browser. (or that's my understanding of it, anyway)
Take http://pastie.org/10242118 and create yourself a favicon file:
dd if=/dev/zero of=favicon.png bs=1M count=4096
gzip -9 favicon.png
you can now crash lots of browsers with minimal bandwidth usage :)
demo: http://dev.tomjepp.uk/