My understanding is that the hourly limit does not apply to the Announce/Discussion lists. In fact, using these lists is normally the first suggestion for those running into the limit with scripts etc.
No, you don't. One of the options during the sign-up process is...
Just a dreamhosters.com sub-domain for now (you can still register a free domain later)!
Save [color=#CC0000][b]$50[/b][/color] on DreamHost hosting using promo code [color=#CC0000][b]SAVEMONEY[/b][/color] ( Click for promo code details )