Frugal ways to Water Indoor Plants While on Vacation

Christmas vacations are always awaited as we usually are out of town for holidays every single time. Holidaying was a bittersweet moment as I was not sure how my indoor plants would do without anyone watering them for 12 long days. I started searching for the frugal ways to water my plants.
I had used quart size zip lock baggies back last year!!! That worked perfect!!

Here the link on how to do.....
http://www.instructables.com/id/A-Cheap-Easy-Leak-Safe-Way-to-Water-Plants-While-O/

During our move, I tossed it somewhere and due to lack of time I had to find another way out. I used Styrofoam cup and gently pierced a very small hole at side near bottom(1/2 inch from bottom) and watched the speed at which the water dripped. I kept it for couple of days to ensure that it did not drain quickly. When this trick worked, I had more cups placed on my pots and they were good to go. No doubt, the thought that my plants would die kept haunting during vacation. I was surprised to see all of them alive except my Sweet Marjoram which kind of died(slowly reviving). The plants which had these cups were just fine, the juice bottle technique quite did not work on my Sweet Marjoram.

I used below technique using juice bottle.....
http://aptgarden.blogspot.com/2008/01/homemade-container-watering-system-no.html

Curry Leaf Plant

Sweet Marjoram 

If you have any other frugal technique to water plants please share. Hm....not sure how this technique would fair in summer time!!