If you're not doing anything heave (and the items you listed don't seem at all compute-intensive) what about one of the netbooks? They're not the highest-powered things out there, but it seems like you may not need that.
You'd presumably want something with docking station capability, so that lets out my beloved Aspire One, AFAIK. But, surely, some of the other lower-priced netbook form factor machines do allow this.
Cheers.