Califone USB Digital Microscope ,$110

10x - 200x magnification with manual focusing from 4" to infinity
Takes image snapshots to appear on a computer screen
USB connection to computers allows for group monitoring and easy image capturing
Fully adjustable, detachable microscope stand
Protective lens barrel
Integrated bright white LEDs for lighting the subject
http://www.bhphotovideo.com/c/product/529825-REG/Califone_CM1_USB_USB_Digital_Microscope.html

Carson Zorb Digital Microscope ,$33

Technical Details
Color: Blue
Digital Microscope
35 times magnification on a 14 inch monitor,43 times on a 17 ich,53 times on a 21 inch.
CD Rom Software
640x480 resolution
USB hook-up

http://www.amazon.com/gp/product/B002PCOM46?ie=UTF8&camp=1789

Celestron 44301 Mini Handheld Digital Microscope

Technical Details
Mini Handheld Digital Microscope Powered by a 2.0 USB Cable, Digital Camera - built-in 1.3MP for Snapshot Images (with up to 5MP with interpolation) and Videos
Power - 15 to 30x, LED Illumination, CD-ROM - Software for Basic Image Capture and Organization as well as Simple Measurement Function (on Windows based operating systems)
Computer Requirements - UVC Plug , Size - 3.5"x1.25" (89 mm x 32 mm), Weight - 2.9 oz (82 g)

http://www.amazon.com/dp/B004IAKOZ4/ref=asc_df_B004IAKOZ41610298?smid=A17MC6HOH9AVE6&tag=nextagusmp0351199-20&linkCode=asn&creative=395105&creativeASIN=B004IAKOZ4

Ken-A-Vision T-1050 Digital Microscope ,$289

The Ken-A-Vision T-1050 Digital Microscope provides a magnification of 20x, 40x, and 100x and has a VGA resolution of 640 x 480. Ideal for teachers and students, in the classroom or in the field, the microscope has a camera that can be detached from the stand for handheld macro image capturing.

http://www.bhphotovideo.com/c/product/697069-REG/Ken_A_Vision_T_1050_T_1050_Digital_Microscope.html

Ken-A-Vision T-19541C Digital Monocular Comprehensive Scope 2 ,$674

Product Highlights
USB Computer Connection
View Specimens on Computer
Two 10x Widefield Eyepieces
1 Diopter
Built-In Camera
Variable Light Control
Mechanical Stage
Protective Coating on Optics
100xS Oil Immersion Objective Lens
Adjustable Light Dimmer

http://www.bhphotovideo.com/c/product/697057-REG/Ken_A_Vision_T_19541C_T_19541C_Digital_Monocular_Comprehensive.html

Dino-Lite Digital Microscope (USB2.0) 0.3MP Resolution 10x~200x Magnification. Touch Capture Feature

Technical Specifications:

Resolution: 640x480 pixels

Interface: USB 2.0

Magnification: 10~220X Variable Magnification

Sensor: Enhanced Color CMOS

Built in Micro Touch (Trigger Button)

Video frame Rate: up to 30 frame-per-second

Illumination: built-in 8 white LED’s

LED on/off controlled by software

Save File format: BMP, JPG, AVI

http://www.pcgears.com/dino-lite-digital-microscope-usb20-03mp-resolution-10x200x-magnification-touch_oid223384.htm

Dino-Lite Digital Microscope (USB 2.0) 0.3MP Resolution 10x~200x Magnification,$ 129

Product Applications
Ideal for a wide variety of practical applications in the classroom, workplace and even home. It can be used for science and engineering work and study, dermatology (skin/scalp) exam, detailed repair, assembly and quality control (i.e. electronics, mechanical, etc), hobbies & collecting (coin, stamp, watch, jewelry, etc), law enforcement (counterfeit ID, crime lab, etc), entertainment or simply as a reading aid. Just use your imagination!
http://www.pcgears.com/dino-lite-digital-microscope-usb-20-03mp-resolution-10x200x-magnification_oid189502.htm