stk500_recv(): programmer not responding

Computer: MacBook 13" running leopard 10.5.7

Arduino software: 0014, 0015, 0016

Arduino Board: Duemilanove

I've had my board for a couple of months. It worked when I first bought it, on the same software and system I'm using now. It's been in it's green plastic for a few months, and when I try to upload now, I get an error:

avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding

I've checked the serial port, board type, and I've tried resetting and starting with the board plugged in.
The transmitting and receiving lights do not flash. The power light is continuously on, and the pin 13 LED flashes once when I push reset.

I've taken the main chip out, and put it back in. There is a hint of corrosion on the chip holder contacts, but I'm not sure if it's enough to cause a problem. It looks like it' only on the top, and the pins should make contact further down.

I've looked over the board and there is no obvious physical defects.

Does anyone have any ideas?

(PS. I tried burning a new bootloader, but without the in-system programmer you are supposed to connect. I don't have one. Is it possible I've just stuffed up the existing bootloader?)

Welcome to the team, dude!! I'm trying to figure that out for almost one month now.. no success :-/
Same specs for all.. except my Mac is an 15"..

Today I tried something that turned out strange:
I got my Windows machine and wrote a small program that waits for some serial data and then print that same data back to the serial. I then connected it to the Mac and started writing things to the serial... turns out the Mac sends everything correctly to the Arduino and it GETS it correctly. The problem is when the data is coming back to the Mac.. the Arduino writes it correctly, but no data is displayed on the mac. That makes me believe I can write to the Serial but not Read from it..