Congratulations. Milestones like followers, reaching a certain reputation level will always keep us motivated and happy. And, when we are happy, we of-course should give something back to Steemit via giveaways.

Once such giveaway is going on from my side as well as I have 500 followers as of 2 days back.
Anyone interested to be part of that, can check below link: https://steemit.com/giveaway/@coolguy123/sbd-giveaway-on-account-of-reaching-500-followers-20171127t16125623z