Proxy sites can be used to access blocked sites. Do a google search with keyword 'proxy sites' and you will get a list of proxy sites.
Proxy sites acts like a middle man between your system and the server you need to access. You resquest the page to be fetched and the proxy fetches it for you. To your system it looks like the data is coming from proxy site, but in actual the proxy will be sending you the data you want in its name.Regards, Sam
Proxy Servers are good options but as you declared that you want some other options.
Generally sites are blocked with keywords and domain names. So, there is a option that you find the IP address of the server you want to connect with by using command 'whois'. Then, in the adress bar of the browser, instead of domain name enter IP address. You will connect to the server.