The built in keyboard and trackpad are designed for portable and emergency uses, not for constant everyday uses.
Logictech has a new mouse out, it's a little USB key with a low profile that remains plugged in, a wireless two button laser mouse comes with it and a battery that lasts 18 months before it has to be replaced.
DAS Keyboard has a nice tough, long lasting (decades even) clicky clack full size keyboard with a long 6 foot USB cable that will sit in your lap while your notebook is sitting comfortably at eye level on a table or desk. It can take a pounding and keep on going when cheap bubble type membrane keyboards (hint Apple's) are long gone.
Both devices take the wear and tear off the machine thus increases it's resale value, are replaceable and much more erogonomic as they allow your body to get into less muscle straining positions.
IMO these are the two best possible products you can buy.