I see some inviting offers recently, and I expect more in the holiday season. It is quite trendy for the provider to throw X GB memory within the LEB budget, so you can host multiple sites in one host.
However, if you care about the users' privacy and go to SSL, the extra IPv4 address usually costs 2$/m; then it makes little sense economically to put multiple eggs in one basket. As some providers even throw 512M for 24$/y with 1 IP address, why additional cost that much?