some great free icons:

large variety of 16x16 png files: http://www.famfamfam.com/lab/icons/silk/


Higher quality icons: 256x256 arranged by theme: http://www.proicons.com/icon_collections.htm

Web page speed check and optimisation

There are at least 3 places where one can check a web page speed, and obtain various recommendations regarding ways to improve page load time:

Google Page Speed Insights

YSlow and here the original yahoo site, with tips on site performance. Firefox addon is available too.

Webpagetest which offers the ability to select a different location for the test and different browsers.

These are certainly useful tools when it comes to web page loading times improvement and optimisation.

Update: Recently I found the site www.modern.ie which seems quite good for checking for valid pages against various browsers, OSes and devices. Not all the functionality is free, but seems reasonably priced for commercial web sites.