Little bottles full of M&Ms or other candy that could look like pills.
Magnetic jewelry to hold your eyeglasses:
http://funpinswork.com/ (You could make them if you wanted to.)
Tissue holders--surely you could stamp something for a cover?!
Greeting cards are always good. That would save a lot of $$ for an elderly person on a budget.
Music CD of "remember when" music. You could even ask her for songs she remembers and find them on iTunes--make a custom CD for your guests. If you wanted to get fancy, you could get someone to play DJ and do a "this was your life in pop music" type of thing.
A potted plant
Hand lotion
Gourmet Teabags
Picture frame
inexpensive corsage for each one
Subscription to Reminisce Magazine or One mag per person
Make a "newspaper" of things that were popular when she was a child, headlines, etc.
Party Favors for 80yo Bday Party?
