With just a little focused shopping you can buy some great gifts for under $20.
I love going to Pier 1 to find great gifts and surprisingly you can find things for under $10. But you don't have to go to Pier 1, you can go to just about any store and find lots of great items for $20 or less. But you have to be imaginative.
In general, I think creating a basket of individualized gifts, hand picked for that person is always a great gift whether for co-worker or friend. Pick a theme. By that I mean pick something that appeals specifically to that person. And don't get hung up on the basket. You can use a traditional basket, but you can also purchase any type of container and just decorate it to match your theme. For example if your co-worker is into boats, light houses - you can find pictures of them or buy a little toy and attach it to the container.
Some idea's for female co-workers:
Candles: Buy different scents and colors of the votive candles.
Lotions, creams, shampoos: Create a basket of sample bottles of lotions, creams, shampoo (etc). You can find samples at Bath & Body Works or at the cosmetic section of the local drugstore. Instead of putting it into a traditional basket, put your items into one of those shower caddies.
Some idea's for male co-workers:
Cologne, after shave, shampoos: Just go to your local department store and ask for samples.
For the handyman or painter: Find some of the tools of their interest or trade: Putty knives, paint stirring sticks, small screwdrivers, car wax, rags, etc.
Create a sample basket of tea's or coffee's or hot chocolate and then add a bag of cookies.
Create a lunch basket and fill it with gift cards from some of the fast food restaurants that are near the office. You may package your items into a lunch bag or a microwave dish.
Make your own fruit basket: Buy a bag of apples, oranges, pears, etc and create your own fruit basket.
Make your own cookie basket: Find the small samples usually child size packages of cookies and candies and put them in a cookie jar.
I created a basket for some friends that are vegans. I went to one of the local whole foods/organic food stores and I bought small packages of food that would make a meal but required very little cooking. I bought boxes of soups, a baguette, salty snacks and organic cookies. I arranged them in a basket with a big ribbon. They were thrilled to try new items and it was something that was created just for them.
Your hardest job is finding out what the co-worker likes to eat, what they do in their spare time, or any of their outside interests. How to package and wrap the item will come to you after you pick a theme.