My recommendation is to go for a contact method just in case you bag get misplaced. An obvious contact would be a mobile phone number, assuming you take it with you on your travels - and so people abroad can figure out how to call you, include the country code; ie +44 7777 777777 for instance.
The tags have space for two lines in addition to your name, so your email address is also a good option for the second line, so your personalisation could be;
Joe Bloggs
+44 7777 777777
[email protected](On the order form, you only need to complete the 2 customised lines, as it assumes the first line will be your name anyway).
I agree with others that it's not really a good idea to put your home address on your tags, as it advertises the fact your not at home at the moment. However, you can put whatever you like on your tags (others have gone for company names, slogans and amusing messages...
)
Pete