OmniDiskSweeper for linux server??

I have a problem where my Linode server sends me an email everyday about how much disk space is left. It’s at 93% now. Does something like OmniDiskSweeper exist for Linux servers?

I don’t want to have to upgrade the whole server at Linode, all I want to upgrade is the disk. I don’t want to use S3 for files because I’m nowhere close to using the max allowed bandwidth for this server.

I’m on the Linode 4096 plan now.