A resume doesn't have to conform to any format or layout or even the information it contains. Admittedly it needs to contain the right content to get you an interview, but that is the only thing it needs. A resume serves no other purpose.
For your situation just put travel in as experience too, it's a perfectly acceptable reason for not working. If your resume uses the subject heading "Work Experience" then change it, to just be "Experience". If you traveled a long way, list the countries you visited too. This entire entry shouldn't be more than 1 bullet point unless you're applying for a travel agent position, as it's fairly irrelevant to most jobs but does give a good explanation for a long gap in working and may provide additional talking points at the interview.
The same can go for any valid reason for unemployment, like studying, volunteer work, injury, etc. Though if the study is relevant to the job you're applying for it should be more than a single line.
People who were fired, lost their house/accommodation, and had to move back in with their parents for several months or more need to be creative. There is nothing saying you have to put dates on your resume at all. Employers mainly want to know how long you did that work for, that's why you see employers asking for things like "have 5 years experience" and not "worked in the industry for the last 5 years". In Australia I believe it is illegal for an employer to ask how old you are before they offer you the job. So if you don't tell them (this includes year of graduation from school), they can't work out if there are gaps.
You can also not use the full date, just include what year it was. So if you stopped work at your last job in say Feb 2013, and it's now Feb 2014, just put that you finished your last job in 2013. To make it look less like you're hiding something make all of you dates of employment like this.