Mini SD Cards can be formatted and reused after a while. They just need to be plugged into a computer through a card reader and having the format disk option run.
Not at all. Many computers these days have an SD card reader built in, but if yours doesn't, just get a USB model from your local big-box store (they usually run about $20)
They run anywhere from $5.95 to $99.99
No, the Wii is not built to run a file off of an SD card as a boot. Hackers use boot files to run something from a usb/sd or other memory storage to hack with just the external memory, so your safe.
225 miles.
185 miles
You can either buy a printer, scanner or other external device that has an SD slot in it, buy an SD interface card that occupies a bay in the computer enclosure or you can buy an SD adapter that plugs directly into a USB port.
I mailed an sd card to Afghanistan and when it arrived it could not be read or reformatted. Basically it ruined my sd card as far as I can tell. not sure what happened.
115 miles
No, homebrew games can't be played like that. The DS can't run code from the SD card, to prevent piracy, unlike the PSP which can run code but only code signed by Sony. In the case of the DS, the SD card just stores data.
about 93.8 miles according to google maps
yes and no... you can put some music on your wii through a SD card or SD mini for photo channel slide show