Free extensions for Joomla!

I have a big sitemap with about 5000 listings - the sitemap often "crash" when i click on it. It would be nice with an option to load sitemap with ajax or JS.

Would work like this,
When this option is choosed then the sitemap would load in intervalls, instead of loading all info it will load in "chunks", displaying the sitemap bit-after-bit depending by how much of the sitemap has been load.

Would this interupt google-bots? Or what do you think about this feature?