Inspiron 14R N4110 Laptop - upgrade options?

My wife's Inspiron 14R has served her well the last 4 years and she really likes the size and features. Anything I can do to breathe some fresh life into it? I don't mind scouring used parts on eBay - kept my Precision 490 ticking for 8 years doing that. What upgrades make the most sense? Memory? Hard drive? CPU? Here's the current configuration: Intel Core i5-2 410M 2.3GHz 4GBx1 1333MHz DDR3 Intel HD Graphics 3000 1.6GB DVM 640GB 5400 RPM SATA HD Thanks for any help/suggestions!