User styles that hide site functionality I don't use. Created with http://sobolev.us/stylish/.

facebook.css

#pagelet_trending_tags_and_topics,
#listsNav,
#appsNav,
#groupsNav,
#interestsNav,
#pagesNav,
#developerNav,
#timeline_info_review_unit,
#pagelet_pymk_timeline,
.recentActivityContainer,
#pagelet_ego_pane {
	display: none;
}

.fbTimelineIndeterminateContent {
	margin-bottom: 0 !important;
}

#pagelet_reminders > .egoOrganicColumn {
	border-top: none !important;
}

twitter.css

.wtf-module.has-content,
.module.trends {
	display: none;
}