How to improve image quality in Firefox when using Sprint Tethering?
Would the same thing happen if you used a VPN? Your ISP wouldn't be able to compress images if it didn't know what the traffic was, right?

I found setting up a basic VPN to be pretty easy; if you have a Win 7 PC with an internet connection (or a willing buddy with one) you can set up a quick VPN using this guide: How to Configure your Computer to Accept Incoming VPN Connections in Windows 7. With that working, try connecting to your VPN both from your tethered laptop and from the Android phone itself. If it works you could investigate a more permanent VPN solution.