Get this package of Pentel EnerGel Deluxe RTX Gel Ink Pens (Assorted Colors, 6 Pack) for just $4.25 right now.  It is priced at $5 as an add-on item, but you can click the little checkbox under the price to apply a 15% coupon.

These are highly-rated and can be refilled!

• High performance ink technology combines the best qualities of liquid and gel ink for a super-smooth writing experience
• Liquid gel ink dries so fast even left handed writers love it – no smears, no smudges, no globs
• Sleek & stylish barrel design with stainless steel accents for a professional look
• Latex-free grip for writing comfort and control
• 0.7mm stainless steel tip writes medium lines
• Retractable and conveniently refillable with Pentel LR7 ink refill.

Please note that these are an add-on item.  Prices may change.  You can see the full deal here.