It sometimes comes up that you want to keep on “Turn URLs and emails into links automatically” for some fields in a weblog and not others. This wasn’t possible previously, but thanks to a plugin created by Rick, it now is.
You can download the plugin here.
To use this, just turn off the auto linking feature in your weblog preferences (Admin -> Weblog Management -> Edit Preferences), then in your templates, surround any field variables you want auto-linked with the plugin:
{exp:auto_linker}
{body}
{/exp:auto_linker}