Just edit your ~/.bashrc and add this at the very end:
export PS1="realtechtalk.com"
Then your prompt will look like this:
bladeblox:uptime
08:47:14 up 48 min, 1 user, load average: 1.00, 1.07, 0.96
If you wanted a dollar sign at the end then you would change it like this:
export PS1=&........