Handy App?

Hi, I've got a question. I'm developing a application that minimizes the time it takes to contact a host on the internet by storing the IP-addresses locally in the hosts.sam file instead of contacting the DNS-server on every connection request. I want to make this app as a exercise for myself, but I want to know if there is any need for such a program because I don't want to make this and afterwards discover that it's useless. I'm on cable-modem with 512 KB/S so for me it doesnt take that long to contact a DNS-server. But for all you guys with 33.6/56K modems, is this app handy? Also, if any of you guys can give me some things that I could add to it (like pinging and things like that), please let me know, because I'm running out of ideas. Thanks.