Fortunately the one I’m getting now is of the first variety, with a nicely sequential number system. I was able to get this down to a single line in bash:

for i in `seq 1402`; do echo “http://comic.com/images/$i.png” >> list; done && wget -P images/ -i list -o log -w 8 –random-wait -U “$UserAgent”

The first part creates a file that lists the links to all of the images (note: those are backticks, not quotation marks, around the sequence command — of course adjust the number there to whatever the most recent # comic is).

The wget parameters are:

-P a prefix to add to the files to save to, in this case an ‘images’ directory
-i imports a list of urls from my “list” file
-o directs all output to log file “log”, so I can scan through for any errors later
-w base the pause time between requests on 8 seconds
–random-wait randomize the pause to between 0.5w and 1.5w (4 and 12 seconds)
-U set the user-agent, in my case this is a variable that gets loaded with bash for just such scripts — this sets how your request looks in their logs

I’ve done scripts like this in bash-only as well as in python. I love scripting this stuff!