Re: Modifying default widgets
function bp_activity_content_filter( $content, $date_recorded, $full_name, $insert_time = true, $filter_words = true, $filter_you = true )
It’s in bp-activity-templatetags.php. Sitewide activity widget calls that for all content being displayed. It updates the ‘time since’ %s placeholder.
That should be the spot to modify it like John suggested. He does pretty well with notepad++.
“somwhere around line 151” is a pretty exact somewhere. 
I’m fooling around with NetBeans IDE 6.5. It has it’s moments of usefulness.
