Not sure if there was already a topic about this, but i could find it, anyways heres what i've found.
WD40 - good for filling medium sized tags
Hair Spray - i've found certain brands to be really fat, while others just clog.
Carb Cleaner - Havent tried it yet, but when on the carb cleaner bottle its a rather focused spay.
not much, but its some ideas, especially if your unable to get caps easily in your area, post yours!