For you if you don't want to make your customer feel that they're reading a standard letter but there are snippets of text that you have to type...
ClipAssist is for you if you don't want to make your customer feel that they're reading a standard letter but there are snippets of text that you have to type regularly; your address, your vat number, directions to your premises, answers to those frequently-asked questions...
Do you type them every time?
I tried clipboard history applications and multi-clip applications but found that these didn't do exactly what I wanted.
ClipAssist will sit in the background and give you quick access to those clips, in unstyled text so that you can paste anywhere with the minimum fuss.
Start up ClipAssist, press the [+] button, give it a name and paste in your first clip. Go to preferences to configure hotkeys. Assign one of the F keys to call ClipAssist to the front for quick access to any of your clips.