Nearly all the major shared hosting companies have a file count limit on their unlimited hosting plans. So even though they say it's unlimited, they put a limit on the total amount of files you can have on your account. Most companies set a limit in the range of 50,000 to 200,000 I am trying to find an unlimited shared hosting plan that allows a file count greater than 200,000
Dont let the negative reviews hold you back, but m2host.com has unlimited inode limit. I dunno where they got their unlimited hard drive from.... (note, by answering your question, I am in no way recommending them, its up to you to decide if they are worth the risk) Good luck
While I'm sure there are hosts who offer higher limits, at what point would it be good to go for a more dedicated solution such as VPS/dedicated/colo? Lots of hosts wont advertise this, so you'll likely need to send in quite a few tickets to build a good list. A large script would usually see no more than 5k files I would assume, and thats likely a very large script. Something to remember is the additional strain required to gather all those files as hosts regularly perform backups of accounts, and this causes the load to increase for a slightly longer period due to allowing everyone to have lots of files. Also that there is a hard-limit for the server for inode count, so there's always going to be some sort of limit for this no matter the host.