How do I make a link to another Dreamwidth account, or an account on another service?

You can use the <user name=username> tag to create a link to another Dreamwidth account. The link you create will look different for a person, a community, or a feed, but in each case the icon will be a link to that account's profile. For example:

DW user: <user name=username> gives username
DW community: <user name=omnomnom> gives omnomnom
Feed account: <user name=xkcd_feed> gives xkcd_feed
OpenID account: <user name=rahaeli.livejournal.com> gives rahaeli.livejournal.com

You can also specify an account on a different site by adding "site=sitename" in the tag, as follows:

<user name=news site=livejournal.com> gives news
<user name=announcements site=insanejournal.com> gives announcements

Alternatively, if you are using Markdown you can use @username to link to username. To link to a user on another site, use @username.sitename.

This feature will work with any site that has specifically been added, or with any site that uses the structure "www.example.com/users/username" for their URLs. Unknown sites will display with a generic icon.

Sites that are currently recognized by this tag are:

archiveofourown.org (also works with ao3.org, archiveofourown, ao3)
blogger.com (also works with blogspot.com, blogger, blogspot)
deadjournal.com (also works with deadjournal, dj)
deviantart.com (also works with deviantart, da)
etsy.com (also works with etsy)
facebook.com (also works with facebook, fb)
fanfiction.net (also works with ffn)
github.com (also works with github)
insanejournal.com (also works with insanejournal, ij)
instagram.com (also works with instagram)
last.fm
livejournal.com (also works with livejournal, lj)
lj.rossia.org (also works with LJR)
medium.com (also works with medium)
pinboard.in (also works with pinboard)
pinterest.com (also works with pinterest)
plurk.com (also works with plurk)
ravelry.com (also works with ravelry)
twitter.com (also works with twitter)
tumblr.com (also works with tumblr)
wordpress.com (also works with wordpress)
youtube.com (also works with youtube)

To request that a site be added, you can make a suggestion.

Official communities and Dreamwidth staff accounts display with different icons, but the method of linking is the same. These official accounts display with different icons to show that they are in some way connected to the process of running Dreamwidth. For example:

DW staff: <user name=denise> gives denise
Official community: <user name=dw_news> gives dw_news

If you're using the Rich Text Editor, enter the account name, then highlight it and select Account. This will automatically generate a link. At the moment this only works for links to users on Dreamwidth.

You can also find the code for this link at the bottom of each user's profile page, along with HTML code to link to them on sites outside Dreamwidth.