Get a reverse ring* so you can mount your prime on your camera reversed to get way beyond 1:1.
Or even more fun, two primes together with the second reversed for really scary super macro.
A classmate did this, more or less, by simply holding a prime against his own lens reversed and took some pictures.
In the pic he took of his laptop screen, the individual red, green and blue lights of the pixels were magnified to about 1cm height each
Also, for uploading a size of 1200x800 pixels is large enough and not as demanding.
*They're pretty cheap, ranging from $15-40, the problem is finding them as they're very specific niche items that only macro photographers will ever use.
Edit: also check out
Thomas Shahan's website, he has some absolutely awesome macro photos. (mainly of spiders, for the arachnophobes here)
Edited, Feb 12th 2011 7:58pm by Aethien