I normally keep a dial-up as spare, incase I reach my cap.
The cellphone GPRS thing also works well, and you dont even pay ISP charges. You also dont pay per minute charges, only the MB you download - it's a "always-on" connection with GPRS.
hit the cap on my 3 gig account so said screw telkom, ordered a 30 gig from web africa, was up in 5 mins and have been a dl fest since last night.... all is good