Scalable Hosting for Side Project

I have a side project which sometimes get many visitors. I initially hosted it on a cheap hosting provider, but on the first surge of visitors it got hugged to death. So I quickly moved to Microsoft Azure, and since then I had no downtime. However Azure have a relatively large monthly cost for such a non-commercial project. It seems more geared towards businesses.

I wonder if there is some alternatives which the HN can recommend? I'm looking for something which can handle a surge but with a lover baseline cost.