Stuff I want to learn and teach to others

Here's what I think everyone should know more about:

online banking - pay pal
IM instant messaging - msn, yahoo, miranda
video chat - ifriends, msn,
skype - VoIP
photo sharing - flickr, picasa, hello
podcasting - doppler, audacity
shared bookmarks - furl.net, del.icio.us
message boards: how to post, how to search, sigs, avatars, etc
online calendars - rsscalendar.com
blogs - blogger, wordPress, radio,
blog readers - aggerators, my yahoo, bloglines, feed burner
wiki - wikipedia

And the things we use everyday too:
browsing - firefox extensions, methods for expert surfing
searching - how do you search?
listening to music - winAmp, and iTunes
email - what's the deal with Gmail


there are the tools of modern communication and the web. Do you have a link or insights to share? Have I left something out? please comment and let me know.