automatically append & to all comands in terminal?

I do not know if this is dangerous for comands that dispaly something in the terminal (I tried grep -r 'something' /somewhere & and it worked fine), but I would like to append to all my commands & automatically (it saves me typing C-z bg everytime I forget)?
Is there a way to do it for all comands? The only way I know would be with aliases in .bashrc, but this would be a bit too cumbersome...

Thanks very much.