Related Clues:
- It may come with attachments
- Much money
- Target of some filters
- Accumulate, with ''up''
- Forward, perhaps
- Where all addresses include @
- What a server may serve
- Letters that can arrive at any time
- Write, these days
- Rub it in, with 'on'
- Office communication
- Virtual inbox filler
- Postal alternative
- Lotsa cash
- Something you click to open