Well I currently use a laptop connected to my cell phone on the Verizon network. It is not fast, but is workable for ssh access. I am hoping a blackberry can perform as well for the times when a laptop is not feasable.
I have used my Blackberry to stop and start services. Of course, it's much easier to do it from a laptop, but for times like you mentioned where a laptop is not available I think SSH over a BB works well.