Speaking from a cancer survivor's perspective, I would avoid loading her up w/ the Pink Ribbon tchotcke's that seem to be everywhere. They may be hip & trendy right now, but will have the unfortunate side effect of sending your mom back into the feelings of turmoil and uncertainty when she is finished with treatments and moving back into her "new normal". During chemo, food tends to taste a bit metallic, and it doesn't improve until well after radiation is over, so don't send her any of her favorite foods, or else she may develop an aversion to them during this time. I used to eat my favorite trail mix during my chemo treatments, and now it literally makes me nauseated to even see it!
A healing meditation CD would be something good to include, since the mind/body connection is HUGE. I also got a lot of good out of fresh juices (juice machine is a big plus!), and perhaps you could help her find a local acupuncturist to aid in reducing some of the side effects from chemo, too. Cranial-sacral massage helped me to visualize my tumor turning into a worm and then watched it shrivel up and die, so that's another good thing to consider.
Finally, make sure that you talk about things other than her treatments. Try to not start every conversation w/ the hushed tones of, "How are you feeling today?". Don't let her obsess over what's going wrong w/ her cells. Help her to understand that LOTS of great stuff is going RIGHT, and that will help you, too!
Feel free to call me at ###-###-#### if you'd like any more advice or a different perspective!