You could try cutting back on your upload bandwidth, that way you would still be sharing instead of freeloading.

In LW go to Tools>Options>Uploads>Basic> then experiment a little to find a setting that works for you. Also set it to automatically clear uploads, then under speed, set it to disable ultrapeer. This will help save some bandwidth. Then you may want to cut back on the number of upload slots. Tools>Options>Uploads>Slots> then set it to 5 or something so you don't have a lot of people waiting in queue. Remember to click apply after making any changes.

But if you really don't want to share, just set your upload slots to 0. You can always set it back when your not using your pc.

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