These are some great ideas. You made mention of the Line 6 X2 wireless system. I currently use the X2 XDS Plus version, and one thing to note about it is that it uses a 9V battery. Now I mention this because 9V is getting to be old skool, and seriously there are very few places that carry chargers for 9V rechargeables (which is recommended). Plus using alkaline batteries, a bassist will not get much more than 45 minutes on continuous play. Now I have used Lithium 9V’s, but they are not recommended for devices like wireless systems, but I literally got 5 months of use on it, and some of that it sat unused (disconnected of course).

Other ideas would be a mini recorder for bass guitars. A musician on the road, or just wants to get some grooves recorded, one of these can be an indispensable device (the good ones can transfer to MP3). Strap locks are a very good investment! Nothing is worse than rocking out on stage and your strap comes off n the middle of a breakdown or solo.