What do you guys use to provide a more sturdy longterm attachment to arduino pin ports while still allowing them to be detached and moved when necessary? I'm currently using jumper cables and the ends of resistors but I'm afraid they might wriggle out.
That is what shields are for - amongst other things
A screw shield.
Crossroads does a screw shield, others do as well I think.
A temporary option that is slightly more robust than individual jumper cables is to use the matching header connectors i.e. a male header connector when you're connecting to an Arduino with female headers, and vice versa. These are easily and cheaply available and can be assembled just by crimping the pin/socket on the end of the wire and pushing it into the housing. This makes it easy to move wires around within the housing as your circuit evolves. The header housings are available in different sizes to suit different numbers of connectors.
Having all the connectors mounted into a single housing makes it much more secure and eliminates the risk of individual wires being dislodged. It also makes it much easier to dismantle and reassemble the project if you want to use the same Arduino for multiple projects.
http://wwww.crossroadsfencing.com/BobuinoRev17/ For more details.
Or male terminated wires in crimp housings from www.pololu.com, they plug into female headers nicely.