I want to see this in my final table -- I click on a box in a field and i get a list of text values in the dropdown box but the last value should be 'other'. By selecting this 'other' I should be able to enter a text by myself.
You cannot use a domain to do this and as far as I know you cannot do this, since it violates the tableview design. You want to violate a coded value domain, which will generate a validation violation when you run Validation for the field. A coded value domain can only be violated with runtime user defined values if the user uses the Field Calculator to insert their own values into the field, not by typing, since all keystrokes in the field simply pick from the domain list. Allowing users to do that makes the domain and any validation useless.
With your design once the user types over the word "other", you would have no way of knowing that they had originally made that choice and then typed over it. They could have just gotten in the habit of using the Field Calculator and unintentionally created unwanted variations or misspellings that are pure violations of your other listed coded values. You would have no help from the built in validation routine to identify which values outside of your domain truly are other and which are just violations of your domain. All validation would require manual intervention and could not be programmed making the domain more or less useless.
Anyway, the standard practice for what you want to do is to include "Other" in the list of options, and when that option is chosen force the user to fill in another field that is optional or blanked out for all other domain values. That can be enforced by an Editor extension or other ArcObjects code and the domain would be able to be enforced using built in validation techniques. Perhaps Attribute Assistant could be used to avoid programming and allow you to configure the validation behaviors of this second field, but it could not help you achieve what you described for the coded value domain behavior. If Attribute Assistant didn't work then I don't know of any other method that can completely avoid custom programming and simply be configured using already built in behaviors of ArcMap.