Mental note to myself (and anyone that I can help):
You can easily add a 'share on Twitter' link in an email (and thus anywhere) with this URL:
- via: the account name of where this originated from
- text: the text you wish to show
- related: not really sure but Twitter describes it as "accounts related to the your content or intention [...]. After Tweeting, the user will be encouraged to follow these accounts."
- source: no idea, apparently can be left empty
This gives this link