Here are some web hosts recommended by users which allow you to install Tracks and therefore use it from any internet-connected computer:

• TextDrive: Where bsag hosts the Tracks project, her blog and her own private version of Tracks. They have all you need to install Rails applications, and great technical support. (note: textdrive has been absorbed by Joyent – don’t know if that changes anything or not…)
• Slicehost: Built for developers. We offer 256/512/1024 Xen VPS Slices with choice of OS (Ubuntu, CentOS, Gentoo). The 256 is perfect for hosting Tracks and we’re big fans. Full root access – run Apache, Lighttpd, Mongrel, Webrick – your choice. Please contact us or pop into the chatroom with any questions.
• Site5: Installed and works without any problem. It allows users to optimize their sites many search engine optimization experts will agree.