The PrinterShare Mobile Print (premium, unlocked version) is Amazon's Free App of the Day. This normally sells for $12.95.
I usually do not recommend apps, but this app I am highly enthused. This app works for both wireless printers and printers connected to a PC. My printer is an Epson Color Stylus 875, an older model, connected by USB cable to my Windows XP PC.
After installing and testing this app, I highly recommend it.
I obtained the premium, unlocked version of PrinterShare Mobile Print as the Amazon "free" app of the day. All together it took me about 10 minutes to install all components and set up the account.
Install PrinterShare Mobile Print from Amazon onto Droid 3
Install 'PrinterShare for Windows' (32-bit) onto my PC running Windows XP (There is a 64-bit for 64-bit Windows 7) (PrinterShare® Print it anytime, anywhere! FREE Download software!)
Select printer(s) within the 'PrinterShare for Windows'
Sign-up for "free" PrinterShare account
Install document rendering software onto Droid 3 (4 mb)
Now you are ready to go.
I printed a small photo and a small MS word (.doc) file on the Epson printer from the Droid 3 and it printed as expected. I also 'printed' a file to Adobe PDF and a .pdf file was created.
There is a slight delay from pressing 'Print' on the Droid 3 until it appears 'ready-to-print' (or auto-prints depending on your print set up on your PC). This delay is based on the size of the document. With the 3 docs, the longest delay was under 2 minutes and it was for the Adobe PDF, the 2 that went straight to print were under 1 minute.
My wife also downloaded and installed PrinterShare Mobile Print. We linked it to the same account on the PC and it worked flawlessly. She especially likes the ease in printing pictures from her Droid 3.
This is a great app.