For finding Waymarks 'on the go' with a mobile phone, try
http://www.chilehead.us/waymarking/ (chilehead.us/wm will link too)
Gives access to the Waymarking site, allows logging (Visit) and to post your own Waymark (or get the relevant photos/ information to do a write up at home.)
It has been set up with the approval of GS. But goes to show what can be done, and could be done so much better with some thought and money by GS themselves, if only they cared!