I've never been fond of trackballs personally. I don't seem to have as much control (though it may be to much control) as with my laser mice (two computers two mice). Both are cordless and I don't have any problems with them till the batteries start to die. Though I only have to replace the batteries every few months or so. On my desktop I have a wireless keyboard and mouse set up by Logitech and the mouse I use with my laptop is also Logitech. I haven't replaced the batteries in my keyboard yet and I've had it a few years.

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"BOY: On a hot summer night, would you offer your throat to the wolf with the red roses? GIRL: Will he offer me his mouth? BOY: Yes. GIRL: Will he offer me his teeth? BOY: Yes. GIRL: Will he offer me his jaws? BOY: Yes. GIRL: Will he offer me his hunger? BOY: Yes. GIRL: Again, will he offer me his hunger? BOY: Yes! GIRL: Yes. BOY: On a hot summer night, would you offer your throat to the wolf with the red roses? GIRL: Yes. BOY: I bet you say that to all the boys!" -Meatloaf